Discourse

Discourse is an open source discussion platform. In versions prior to 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0, non-admin moderators can view sensitive information in staff action logs that should be restricted to administrators only. The exposed information includes webhook payload URLs and secrets, API key details, site setting changes, private message content, restricted category names and structures, and private chat channel titles. This allows moderators to bypass intended access controls and extract confidential data by monitoring the staff action logs. With leaked webhook secrets, an attacker could potentially spoof webhook events to integrated services. This issue is patched in versions 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0. As a workaround, site administrators should review and limit moderator appointments to fully trusted users. There is no configuration-based workaround to prevent this access.

Published: 2026-01-28T20:11:30.982Z
Updated: 2026-01-28T20:35:27.216Z

Discourse is an open source discussion platform. In versions prior to 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0, permalinks pointing to access-restricted resources (private topics, categories, posts, or hidden tags) were redirecting users to URLs containing the resource slug, even when the user didn't have access to view the resource. This leaked potentially sensitive information (e.g., private topic titles) via the redirect Location header and the 404 page's search box. This issue is patched in versions 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0. No known workarounds are available.

Published: 2026-01-28T20:07:21.266Z
Updated: 2026-01-28T21:07:37.739Z

Discourse is an open source discussion platform. In versions prior to 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0, moderators can convert some personal messages to public topics when they shouldn't have access. This issue is patched in versions 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0. As a workaround, site admin can temporarily revoke the moderation role from untrusted moderators or remove the moderator group from the "personal message enabled groups" site setting until the Discourse instance has been upgraded to a version that has been patched.

Published: 2026-01-28T19:51:37.991Z
Updated: 2026-01-28T20:10:06.915Z

Discourse is an open source discussion platform. A privilege escalation vulnerability in versions prior to 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0 allows a non-admin moderator to bypass email-change restrictions, allowing a takeover of non-staff accounts. This issue is patched in versions 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0. As a workaround, ensure moderators are trusted or enable the "require_change_email_confirmation" setting.

Published: 2026-01-28T19:33:58.921Z
Updated: 2026-01-28T20:15:03.696Z

Discourse is an open source discussion platform. In versions prior to 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0, moderators can access the `top_uploads` admin report which should be restricted to admins only. This report displays direct URLs to all uploaded files on the site, including sensitive content such as user data exports, admin backups, and other private attachments that moderators should not have access to. This issue is patched in versions 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0. There is no workaround. Limit moderator privileges to trusted users until the patch is applied.

Published: 2026-01-28T19:30:28.793Z
Updated: 2026-01-28T19:45:12.386Z

Discourse is an open source discussion platform. In versions prior to 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0, authenticated users can submit crafted payloads to /drafts.json that cause O(n^2) processing in Base62.decode, tying up workers for 35-60 seconds per request. This affects all users as the shared worker pool becomes exhausted. This issue is patched in versions 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0. Lowering the max_draft_length site setting reduces attack surface but does not fully mitigate the issue, as payloads under the limit can still trigger the slow code path.

Published: 2026-01-28T19:19:59.627Z
Updated: 2026-01-28T19:46:16.472Z

Discourse is an open source discussion platform. In versions prior to 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0, non-admin moderators with the `moderators_change_post_ownership` setting enabled can change ownership of posts in private messages and restricted categories they cannot access, then export their data to view the content. This is a broken access control vulnerability affecting sites that grant moderators post ownership transfer permissions. This issue is patched in versions 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0. The patch adds visibility checks for both the topic and posts before allowing ownership transfer. As a workaround, disable the `moderators_change_post_ownership` site setting to prevent non-admin moderators from using the post ownership transfer feature.

Published: 2026-01-28T19:17:23.713Z
Updated: 2026-01-28T20:16:21.375Z

Discourse is an open source discussion platform. In versions prior to 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0, users archives are viewable by users with moderation privileges even though moderators should not have access to the archives. Private topic/post content made by the users are leaked through the archives leading to a breach of confidentiality. This issue is patched in versions 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0. To work around this problem, a site admin can temporarily revoke the moderation role from all moderators until the Discourse instance has been upgraded to a version that has been patched.

Published: 2026-01-28T19:14:09.984Z
Updated: 2026-02-26T14:58:41.984Z

Discourse is an open source discussion platform. In versions prior to 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0, a hostname validation issue in FinalDestination could allow bypassing SSRF protections under certain conditions. This issue is patched in versions 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0. No known workarounds are available.

Published: 2026-01-28T19:12:24.903Z
Updated: 2026-01-28T20:21:50.707Z

Discourse is an open source discussion platform. In versions prior to 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0, an endpoint lets any authenticated user bypass the ai_discover_persona access controls and gain ongoing DM access to personas that may be wired to staff-only categories, RAG document sets, or automated tooling, enabling unauthorized data disclosure. Because the controller also accepts arbitrary user_id, an attacker can impersonate other accounts to trigger unwanted AI conversations on their behalf, generating confusing or abusive PM traffic. This issue is patched in versions 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0. No known workarounds are available.

Published: 2026-01-28T18:55:11.557Z
Updated: 2026-01-28T19:27:18.739Z

Discourse is an open source discussion platform. Versions prior to 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0 have an application level denial of service vulnerabilityin the username change functionality at try.discourse.org. The vulnerability allows attackers to cause noticeable server delays and resource exhaustion by sending large JSON payloads to the username preference endpoint PUT /u//preferences/username, resulting in degraded performance for other users and endpoints. This issue is patched in versions 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0. No known workarounds are available.

Published: 2026-01-28T18:51:40.341Z
Updated: 2026-01-28T20:20:41.258Z

Discourse is an open source discussion platform. In versions prior to 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0, some subscription endpoints lack proper checking for ownership before making changes. This issue is patched in versions 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0. No known workarounds are available.

Published: 2026-01-28T18:34:00.486Z
Updated: 2026-01-29T18:11:42.379Z

Discourse is an open source discussion platform. Versions prior to 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0 have a content-security-policy-mitigated cross-site scriptinv vulnerability on the Discourse Math plugin when using its KaTeX variant. This issue is patched in versions 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0. As a workaround, the Discourse Math plugin can be disabled, or the Mathjax provider can be used instead of KaTeX.

Published: 2026-01-28T18:21:35.379Z
Updated: 2026-01-28T19:28:24.714Z

Discourse is an open source discussion platform. A vulnerability present in versions prior to 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0 affects anyone who uses S3 for uploads. While scripts may be executed, they will only be run in the context of the S3/CDN domain, with no site credentials. Versions 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0 fix the issue. As a workaround, disallow html or xml files for uploads in authorized_extensions. For existing html xml uploads, site owners can consider deleting them.

Published: 2026-01-28T18:15:52.902Z
Updated: 2026-01-28T19:29:11.123Z

Discourse is an open source discussion platform. Version before 3.6.2 and 3.6.0.beta2, default Cache-Control response header with value no-store, no-cache was missing from error responses. This may caused unintended caching of those responses by proxies potentially leading to cache poisoning attacks. This vulnerability is fixed in 3.6.2 and 3.6.0.beta2.

Published: 2025-10-28T20:38:54.753Z
Updated: 2025-10-29T13:43:00.335Z

Discourse is an open-source community discussion platform. In versions 3.5.0 and below, malicious meta-commands could be embedded in a backup dump and executed during restore. In multisite setups, this allowed an admin of one site to access data or credentials from other sites. This issue is fixed in version 3.5.1.

Published: 2025-10-01T20:41:45.833Z
Updated: 2025-10-02T15:56:54.652Z

Discourse is an open-source community discussion platform. In versions 3.5.0 and below, the Discourse AI suggestion endpoints for topic “Title”, “Category”, and “Tags” allowed authenticated users to extract information about topics that they weren’t authorized to access. By modifying the “topic_id” value in API requests to the AI suggestion endpoints, users could target specific restricted topics. The AI model’s responses then disclosed information that the authenticated user couldn’t normally access. This issue is fixed in version 3.5.1. To workaround this issue, users can restrict group access to the AI helper feature through the "composer_ai_helper_allowed_groups" and "post_ai_helper_allowed_groups" site settings.

Published: 2025-10-01T18:48:55.853Z
Updated: 2025-10-23T13:20:54.766Z

Discourse is an open-source community discussion platform. Versions 3.5.0 and below are vulnerable to XSS attacks through parsing and rendering of chat channel titles and chat thread titles via the quote message functionality when using the rich text editor. This issue is fixed in version 3.5.1.

Published: 2025-10-01T18:42:54.700Z
Updated: 2025-10-01T19:24:29.602Z

Discourse is an open-source community discussion platform. Prior to version 3.4.7 on the `stable` branch and version 3.5.0.beta.8 on the `tests-passed` branch, upon issuing a physical security key for 2FA, the server generates a WebAuthn challenge, which the client signs. The challenge is not cleared from the user’s session after authentication, potentially allowing reuse and increasing security risk. This is fixed in versions 3.4.7 and 3.5.0.beta.8.

Published: 2025-07-29T19:24:06.076Z
Updated: 2025-07-29T19:33:43.304Z

Discourse is an open-source discussion platform. The visibility of posts typed `whisper` is controlled via the `whispers_allowed_groups` site setting. Only users that belong to groups specified in the site setting are allowed to view posts typed `whisper`. However, it has been discovered that users of versions prior to 3.4.6 on the `stable` branch and prior to 3.5.0.beta8-dev on the `tests-passed` branch can continue to see their own whispers even after losing visibility of posts typed `whisper`. This issue is patched in versions 3.4.6 and 3.5.0.beta8-dev. No known workarounds are available.

Published: 2025-06-25T15:39:01.328Z
Updated: 2025-06-26T19:44:55.771Z

Discourse is an open-source discussion platform. Prior to version 3.4.4 of the `stable` branch, version 3.5.0.beta5 of the `beta` branch, and version 3.5.0.beta6-dev of the `tests-passed` branch, Codepen is present in the default `allowed_iframes` site setting, and it can potentially auto-run arbitrary JS in the iframe scope, which is unintended. This issue is patched in version 3.4.4 of the `stable` branch, version 3.5.0.beta5 of the `beta` branch, and version 3.5.0.beta6-dev of the `tests-passed` branch. As a workaround, the Codepen prefix can be removed from a site's `allowed_iframes`.

Published: 2025-06-09T12:36:29.651Z
Updated: 2025-06-09T15:17:08.586Z

Discourse is an open-source discussion platform. Prior to version 3.4.4 of the `stable` branch, version 3.5.0.beta5 of the `beta` branch, and version 3.5.0.beta6-dev of the `tests-passed` branch, certain invites via email may result in HTML injection in the email body if the topic title includes HTML. This includes inviting someone (without an account) to a PM and inviting someone (without an account) to a topic with a custom message. This issue is patched in version 3.4.4 of the `stable` branch, version 3.5.0.beta5 of the `beta` branch, and version 3.5.0.beta6-dev of the `tests-passed` branch. This can be worked around if the relevant templates are overridden without `{topic_title}`.

Published: 2025-06-09T12:33:57.870Z
Updated: 2025-06-09T13:00:15.272Z

Discourse is an open-source discussion platform. Prior to version 3.4.4 of the `stable` branch, version 3.5.0.beta5 of the `beta` branch, and version 3.5.0.beta6-dev of the `tests-passed` branch, sending a malicious URL in a PM to a bot user can cause a reduced the availability of a Discourse instance. This issue is patched in version 3.4.4 of the `stable` branch, version 3.5.0.beta5 of the `beta` branch, and version 3.5.0.beta6-dev of the `tests-passed` branch. No known workarounds are available.

Published: 2025-06-09T12:30:33.626Z
Updated: 2025-06-09T13:01:18.409Z

Discourse is an open-source discussion platform. Prior to versions 3.4.3 on the stable branch and 3.5.0.beta3 on the beta branch, the users limit for a DM can be bypassed, thus giving the ability to potentially create a DM with every user from a site in it. This issue has been patched in stable version 3.4.3 and beta version 3.5.0.beta3.

Published: 2025-04-30T14:55:21.473Z
Updated: 2025-04-30T15:08:52.268Z

Discourse is an open-source discussion platform. Prior to versions `3.3.4` on the `stable` branch and `3.4.0.beta5` on the `beta` branch, in specific circumstances, users could be added to group direct messages despite disabling direct messaging in their preferences. Versions `3.3.4` and `3.4.0.beta5` contain a patch for the issue. A workaround is available. If a user disables chat in their preferences then they cannot be added to new group chats.

Published: 2025-03-26T14:15:13.164Z
Updated: 2025-03-26T18:25:38.709Z

Discourse is an open-source discussion platform. Prior to versions `3.3.4` on the `stable` branch and `3.4.0.beta5` on the `beta` branch, someone who is about to reach the limit of users in a group DM may send requests to add new users in parallel. The requests might all go through ignoring the limit due to a race condition. The patch in versions `3.3.4` and `3.4.0.beta5` uses the `lock` step in service to wrap part of the `add_users_to_channel` service inside a distributed lock/mutex in order to avoid the race condition.

Published: 2025-03-26T14:08:38.915Z
Updated: 2025-03-26T18:26:18.555Z

Discourse is an open source platform for community discussion. In affected versions an attacker can carefully craft a request with the right request headers to poison the anonymous cache (for example, the cache may have a response with missing preloaded data). This issue only affects anonymous visitors of the site. This problem has been patched in the latest version of Discourse. Users are advised to upgrade. Users unable to upgrade may disable anonymous cache by setting the `DISCOURSE_DISABLE_ANON_CACHE` environment variable to a non-empty value.

Published: 2025-02-04T20:48:53.343Z
Updated: 2025-02-12T14:02:29.566Z

Discourse is an open source platform for community discussion. In affected versions an attacker can execute arbitrary JavaScript on users' browsers by posting a malicious video placeholder html element. This issue only affects sites with CSP disabled. This problem has been patched in the latest version of Discourse. Users are advised to upgrade. Users unable to upgrade should enable CSP.

Published: 2025-02-04T20:51:56.909Z
Updated: 2025-02-12T14:03:25.855Z

Discourse is an open source platform for community discussion. An attacker can execute arbitrary JavaScript on users' browsers by posting a maliciously crafted onebox url. This issue only affects sites with CSP disabled. This problem has been patched in the latest version of Discourse. Users are advised to upgrade. Users unable to upgrade should enable CSP, disable inline Oneboxes globally, or allow specific domains for Oneboxing.

Published: 2025-02-04T20:55:17.223Z
Updated: 2025-02-12T14:03:59.537Z

Discourse is an open source platform for community discussion. PM titles and metadata can be read by other users when the "PM tags allowed for groups" option is enabled, the other user is a member of a group added to this option, and the PM has been tagged. This issue has been patched in the latest `stable`, `beta` and `tests-passed` versions of Discourse. Users are advised to upgrade. Users unable to upgrade should remove all groups from the the "PM tags allowed for groups" option.

Published: 2025-02-04T20:59:13.464Z
Updated: 2025-02-05T15:06:02.360Z

Discourse is an open source platform for community discussion. In affected versions an attacker can make craft an XHR request to poison the anonymous cache (for example, the cache may have a response with missing preloaded data). This issue only affects anonymous visitors of the site. This problem has been patched in the latest version of Discourse. Users are advised to upgrade. Users unable to upgrade should disable anonymous cache by setting the `DISCOURSE_DISABLE_ANON_CACHE` environment variable to a non-empty value.

Published: 2025-02-04T21:01:59.746Z
Updated: 2025-02-04T21:23:21.326Z

Discourse is an open source platform for community discussion. In affected versions users who disable chat in preferences could still be reachable in some cases. This problem has been patched in the latest version of Discourse. Users are advised to upgrade. Users unable to upgrade should disable the chat plugin within site settings.

Published: 2025-02-04T21:12:23.126Z
Updated: 2025-02-04T21:41:27.327Z

Discourse is an open source platform for community discussion. This vulnerability only impacts Discourse instances configured to use `FileStore::LocalStore` which means uploads and backups are stored locally on disk. If an attacker knows the name of the Discourse backup file, the attacker can trick nginx into sending the Discourse backup file with a well crafted request. This issue is patched in the latest stable, beta and tests-passed versions of Discourse. Users are advised to upgrade. Users unable to upgrade can either 1. Download all local backups on to another storage device, disable the `enable_backups` site setting and delete all backups until the site has been upgraded to pull in the fix. Or 2. Change the `backup_location` site setting to `s3` so that backups are stored and downloaded directly from S3.

Published: 2024-12-19T19:11:20.590Z
Updated: 2024-12-20T20:43:11.036Z

Discourse is an open source platform for community discussion. In affected versions the endpoint for generating inline oneboxes for URLs wasn't enforcing limits on the number of URLs that it accepted, allowing a malicious user to inflict denial of service on some parts of the app. This vulnerability is only exploitable by authenticated users. This issue has been patched in the latest stable, beta and tests-passed versions of Discourse. Users are advised to upgrade. Users unable to upgrade should turn off the `enable inline onebox on all domains` site setting and remove all entries from the `allowed inline onebox domains` site setting.

Published: 2025-02-04T21:16:42.089Z
Updated: 2025-02-04T21:40:59.102Z

Discourse is an open source platform for community discussion. In affected versions with some combinations of plugins, and with CSP disabled, activity streams in the user's profile page may be vulnerable to XSS. This has been patched in the latest version of Discourse core. Users are advised to upgrade. Users unable to upgrade should ensure CSP is enabled.

Published: 2025-02-04T21:18:19.591Z
Updated: 2025-02-04T21:40:25.211Z

Discourse is an open source platform for community discussion. Users clicking on the lightbox thumbnails could be affected. This problem is patched in the latest version of Discourse. Users are advised to upgrade. There are no known workarounds for this vulnerability.

Published: 2024-12-19T19:12:29.589Z
Updated: 2024-12-20T20:42:25.778Z

Discourse is an open source platform for community discussion. Moderators can see the Screened emails list in the admin dashboard, and through that can learn the email of a user. This problem is patched in the latest version of Discourse. Users unable to upgrade should remove moderator role from untrusted users.

Published: 2024-12-19T19:13:51.333Z
Updated: 2024-12-20T20:01:32.479Z

Discourse is an open source platform for community discussion. Sites that are using discourse connect but still have local logins enabled could allow attackers to bypass discourse connect to create accounts and login. This problem is patched in the latest version of Discourse. Users unable to upgrade who are using discourse connect may disable all other login methods as a workaround.

Published: 2024-12-19T19:15:11.497Z
Updated: 2024-12-20T20:00:41.125Z

Discourse is an open source platform for community discussion. An attacker can make several XHR requests until the cache is poisoned with a response without any preloaded data. This issue only affects anonymous visitors of the site. This problem has been patched in the latest version of Discourse. Users are advised to upgrade. Users unable to upgrade should disable anonymous cache by setting the `DISCOURSE_DISABLE_ANON_CACHE` environment variable to a non-empty value.

Published: 2024-10-08T18:01:14.063Z
Updated: 2024-10-08T18:16:18.149Z

Discourse is an open source platform for community discussion. An attacker can execute arbitrary JavaScript on users' browsers by sending a maliciously crafted chat message and replying to it. This issue only affects sites with CSP disabled. This problem is patched in the latest version of Discourse. All users are advised to upgrade. Users unable to upgrade should ensure CSP is enabled on the forum. Users who do upgrade should also consider enabling a CSP as well as a proactive measure.

Published: 2024-10-07T20:50:33.324Z
Updated: 2024-10-08T14:26:22.147Z

Discourse is an open source platform for community discussion. Users can see topics with a hidden tag if they know the label/name of that tag. This issue has been patched in the latest stable, beta and tests-passed version of Discourse. All users area are advised to upgrade. There are no known workarounds for this vulnerability.

Published: 2024-10-07T20:24:05.044Z
Updated: 2024-10-08T18:13:28.994Z

Discourse is an open source platform for community discussion. A maliciously crafted email address could allow an attacker to bypass domain-based restrictions and gain access to private sites, categories and/or groups. This issue has been patched in the latest stable, beta and tests-passed version of Discourse. All users area are advised to upgrade. There are no known workarounds for this vulnerability.

Published: 2024-10-07T20:23:01.955Z
Updated: 2024-10-08T18:26:35.183Z

Discourse is an open source platform for community discussion. A user can create a post with many replies, and then attempt to fetch them all at once. This can potentially reduce the availability of a Discourse instance. This problem has been patched in the latest version of Discourse. All users area are advised to upgrade. There are no known workarounds for this vulnerability.

Published: 2024-10-07T20:24:32.007Z
Updated: 2024-10-08T18:11:24.827Z

Discourse is an open source discussion platform. Prior to 3.2.5 and 3.3.0.beta5, the vulnerability allows an attacker to inject iframes from any domain, bypassing the intended restrictions enforced by the allowed_iframes setting. This vulnerability is fixed in 3.2.5 and 3.3.0.beta5.

Published: 2024-07-30T14:33:48.589Z
Updated: 2024-08-02T04:19:20.670Z

Discourse is an open source platform for community discussion. In affected versions by creating replacement words with an almost unlimited number of characters, a moderator can reduce the availability of a Discourse instance. This issue has been addressed in stable version 3.2.3 and in current betas. Users are advised to upgrade. Users unable to upgrade may manually remove the long watched words either via SQL or Rails console.

Published: 2024-07-15T19:43:04.811Z
Updated: 2024-08-02T04:04:25.127Z

Discourse is an open source discussion platform. Prior to 3.2.5 and 3.3.0.beta5, crafting requests to submit very long tag group names can reduce the availability of a Discourse instance. This vulnerability is fixed in 3.2.5 and 3.3.0.beta5.

Published: 2024-07-30T14:22:36.367Z
Updated: 2024-08-02T03:50:55.878Z

Discourse is an open source discussion platform. Prior to 3.2.3 and 3.3.0.beta3, improperly sanitized Onebox data could lead to an XSS vulnerability in some situations. This vulnerability only affects Discourse instances which have disabled the default Content Security Policy. This vulnerability is fixed in 3.2.3 and 3.3.0.beta3.

Published: 2024-07-30T14:10:24.804Z
Updated: 2024-08-02T03:50:55.188Z

Discourse is an open-source discussion platform. Prior to version 3.2.3 on the `stable` branch and version 3.3.0.beta4 on the `beta` and `tests-passed` branches, a malicious actor could get the FastImage library to redirect requests to an internal Discourse IP. This issue is patched in version 3.2.3 on the `stable` branch and version 3.3.0.beta4 on the `beta` and `tests-passed` branches. No known workarounds are available.

Published: 2024-07-03T19:13:42.868Z
Updated: 2024-08-02T03:50:55.878Z

Discourse is an open-source discussion platform. Prior to version 3.2.3 on the `stable` branch and version 3.3.0.beta4 on the `beta` and `tests-passed` branches, moderators using the review queue to review users may see a users email address even when the Allow moderators to view email addresses setting is disabled. This issue is patched in version 3.2.3 on the `stable` branch and version 3.3.0.beta4 on the `beta` and `tests-passed` branches. As possible workarounds, either prevent moderators from accessing the review queue or disable the approve suspect users site setting and the must approve users site setting to prevent users from being added to the review queue.

Published: 2024-07-03T19:10:45.955Z
Updated: 2024-08-02T03:30:13.046Z

Discourse is an open-source discussion platform. Prior to version 3.2.3 on the `stable` branch, version 3.3.0.beta3 on the `beta` branch, and version 3.3.0.beta4-dev on the `tests-passed` branch, a rogue staff user could suspend other staff users preventing them from logging in to the site. The issue is patched in version 3.2.3 on the `stable` branch, version 3.3.0.beta3 on the `beta` branch, and version 3.3.0.beta4-dev on the `tests-passed` branch. No known workarounds are available.

Published: 2024-07-03T19:07:27.133Z
Updated: 2024-08-02T03:30:13.048Z

Discourse is an open-source discussion platform. Prior to version 3.2.3 on the `stable` branch and version 3.3.0.beta3 on the `tests-passed` branch, an attacker can execute arbitrary JavaScript on users’ browsers by posting a specific URL containing maliciously crafted meta tags. This issue only affects sites with Content Security Polic (CSP) disabled. The problem has been patched in version 3.2.3 on the `stable` branch and version 3.3.0.beta3 on the `tests-passed` branch. As a workaround, ensure CSP is enabled on the forum.

Published: 2024-07-03T18:23:10.179Z
Updated: 2024-08-02T03:07:46.903Z

Discourse is an open-source discussion platform. Prior to version 3.2.3 on the `stable` branch and version 3.3.0.beta3 on the `tests-passed` branch, Oneboxing against a carefully crafted malicious URL can reduce the availability of a Discourse instance. The problem has been patched in version 3.2.3 on the `stable` branch and version 3.3.0.beta3 on the `tests-passed` branch. There are no known workarounds available for this vulnerability.

Published: 2024-07-03T17:39:38.293Z
Updated: 2024-08-02T03:07:46.876Z

Discourse is an open source platform for community discussion. In affected versions an attacker can learn that secret categories exist when they have backgrounds set. The issue is patched in the latest stable, beta and tests-passed version of Discourse. Users are advised to upgrade. Users unable to upgrade should temporarily remove category backgrounds.

Published: 2024-03-15T19:21:01.130Z
Updated: 2024-08-26T15:02:31.216Z

Discourse is an open source platform for community discussion. In affected versions the endpoints for suspending users, silencing users and exporting CSV files weren't enforcing limits on the sizes of the parameters that they accept. This could lead to excessive resource consumption which could render an instance inoperable. A site could be disrupted by either a malicious moderator on the same site or a malicious staff member on another site in the same multisite cluster. This issue is patched in the latest stable, beta and tests-passed versions of Discourse. Users are advised to upgrade. There are no known workarounds for this vulnerability.

Published: 2024-03-15T19:21:49.443Z
Updated: 2024-08-02T00:27:59.432Z

Discourse is an open source platform for community discussion. In affected versions users that are allowed to invite others can inject arbitrarily large data in parameters used in the invite route. The problem has been patched in the latest version of Discourse. Users are advised to upgrade. Users unable to upgrade should disable invites or restrict access to them using the `invite allowed groups` site setting.

Published: 2024-03-15T19:22:46.937Z
Updated: 2024-08-21T23:12:39.336Z

Discourse is an open source platform for community discussion. Without a rate limit on the POST /uploads endpoint, it makes it easier for an attacker to carry out a DoS attack on the server since creating an upload can be a resource intensive process. Do note that the impact varies from site to site as various site settings like `max_image_size_kb`, `max_attachment_size_kb` and `max_image_megapixels` will determine the amount of resources used when creating an upload. The issue is patched in the latest stable, beta and tests-passed version of Discourse. Users are advised to upgrade. Users unable to upgrade should reduce `max_image_size_kb`, `max_attachment_size_kb` and `max_image_megapixels` as smaller uploads require less resources to process. Alternatively, `client_max_body_size` can be reduced in Nginx to prevent large uploads from reaching the server.

Published: 2024-03-15T19:13:43.221Z
Updated: 2025-04-10T20:27:16.048Z

Discourse is an open source platform for community discussion. In affected versions an attacker can learn that a secret subcategory exists under a public category which has no public subcategories. The issue is patched in the latest stable, beta and tests-passed version of Discourse. Users are advised to upgrade. There are no known workarounds for this vulnerability.

Published: 2024-03-15T19:15:17.121Z
Updated: 2024-08-27T19:43:50.659Z

Discourse is an open-source discussion platform. Improperly sanitized user input could lead to an XSS vulnerability in some situations. This vulnerability only affects Discourse instances which have disabled the default Content Security Policy. The vulnerability is patched in 3.1.5 and 3.2.0.beta5. As a workaround, ensure Content Security Policy is enabled and does not include `unsafe-inline`.

Published: 2024-01-30T21:31:35.617Z
Updated: 2024-10-17T17:59:10.354Z

Discourse is a platform for community discussion. For fields that are client editable, limits on sizes are not imposed. This allows a malicious actor to cause a Discourse instance to use excessive disk space and also often excessive bandwidth. The issue is patched 3.1.4 and 3.2.0.beta4.

Published: 2024-01-12T20:46:00.196Z
Updated: 2025-06-03T14:03:56.412Z

Discourse is a platform for community discussion. Under very specific circumstances, secure upload URLs associated with posts can be accessed by guest users even when login is required. This vulnerability has been patched in 3.2.0.beta4 and 3.1.4.

Published: 2024-01-12T20:53:53.163Z
Updated: 2025-06-17T21:09:17.903Z

Discourse is a platform for community discussion. The message serializer uses the full list of expanded chat mentions (@all and @here) which can lead to a very long array of users. This issue was patched in versions 3.1.4 and beta 3.2.0.beta5.

Published: 2024-01-12T20:35:02.394Z
Updated: 2025-06-17T21:09:17.756Z

Discourse is an open source platform for community discussion. Prior to version 3.1.3 of the `stable` branch and version 3.2.0.beta3 of the `beta` and `tests-passed` branches, the embedding feature is susceptible to server side request forgery. The issue is patched in version 3.1.3 of the `stable` branch and version 3.2.0.beta3 of the `beta` and `tests-passed` branches. As a workaround, disable the Embedding feature.

Published: 2023-11-10T15:13:42.254Z
Updated: 2025-02-27T20:33:47.097Z

Discourse is an open source platform for community discussion. In versions 3.1.0 through 3.1.2 of the `stable` branch and versions 3.1.0,beta6 through 3.2.0.beta2 of the `beta` and `tests-passed` branches, Redis memory can be depleted by crafting a site with an abnormally long favicon URL and drafting multiple posts which Onebox it. The issue is patched in version 3.1.3 of the `stable` branch and version 3.2.0.beta3 of the `beta` and `tests-passed` branches. There are no known workarounds.

Published: 2023-11-10T15:09:54.389Z
Updated: 2024-09-03T18:55:29.162Z

Discourse is an open source platform for community discussion. Prior to version 3.1.3 of the `stable` branch and version 3.2.0.beta3 of the `beta` and `tests-passed` branches, some links can inject arbitrary HTML tags when rendered through our Onebox engine. The issue is patched in version 3.1.3 of the `stable` branch and version 3.2.0.beta3 of the `beta` and `tests-passed` branches. There are no known workarounds.

Published: 2023-11-10T15:00:38.158Z
Updated: 2024-09-03T18:56:52.373Z

Discourse is an open source platform for community discussion. Prior to version 3.1.3 of the `stable` branch and version 3.2.0.beta3 of the `beta` and `tests-passed` branches, some theme components allow users to add svgs with unlimited `height` attributes, and this can affect the availability of subsequent replies in a topic. Most Discourse instances are unaffected, only instances with the svgbob or the mermaid theme component are within scope. The issue is patched in version 3.1.3 of the `stable` branch and version 3.2.0.beta3 of the `beta` and `tests-passed` branches. As a workaround, disable or remove the relevant theme components.

Published: 2023-11-10T14:54:48.828Z
Updated: 2024-09-03T18:57:10.938Z

Discourse is an open source platform for community discussion. Prior to version 3.1.3 of the `stable` branch and version 3.2.0.beta3 of the `beta` and `tests-passed` branches, there is an edge case where a bookmark reminder is sent and an unread notification is generated, but the underlying bookmarkable (e.g. post, topic, chat message) security has changed, making it so the user can no longer access the underlying resource. As of version 3.1.3 of the `stable` branch and version 3.2.0.beta3 of the `beta` and `tests-passed` branches, bookmark reminders are now no longer sent if the user does not have access to the underlying bookmarkable, and also the unread bookmark notifications are always filtered by access. There are no known workarounds.

Published: 2023-11-10T14:49:27.544Z
Updated: 2024-09-03T17:43:21.614Z

Discourse is an open source platform for community discussion. Prior to version 3.1.3 of the `stable` branch and version 3.2.0.beta3 of the `beta` and `tests-passed` branches, if a user has been quoted and uses a `|` in their full name, they might be able to trigger a bug that generates a lot of duplicate content in all the posts they've been quoted by updating their full name again. Version 3.1.3 of the `stable` branch and version 3.2.0.beta3 of the `beta` and `tests-passed` branches contain a patch for this issue. No known workaround exists, although one can stop the "bleeding" by ensuring users only use alphanumeric characters in their full name field.

Published: 2023-11-10T14:43:37.657Z
Updated: 2024-09-03T17:43:41.680Z

Discourse is an open source community platform. In affected versions any user can create a topic and add arbitrary custom fields to a topic. The severity of this vulnerability depends on what plugins are installed and how the plugins uses topic custom fields. For a default Discourse installation with the default plugins, this vulnerability has no impact. The problem has been patched in the latest version of Discourse. Users are advised to update to version 3.1.1 if they are on the stable branch or 3.2.0.beta2 if they are on the beta branch. Users unable to upgrade should disable any plugins that access topic custom fields.

Published: 2023-10-16T20:26:25.200Z
Updated: 2024-09-13T19:00:16.296Z

Discourse is an open source platform for community discussion. New chat messages can be read by making an unauthenticated POST request to MessageBus. This issue is patched in the 3.1.1 stable and 3.2.0.beta2 versions of Discourse. Users are advised to upgrade. There are no known workarounds for this vulnerability.

Published: 2023-10-16T21:24:10.688Z
Updated: 2024-09-16T15:41:43.734Z

Discourse is an open source platform for community discussion. User summaries are accessible for anonymous users even when `hide_user_profiles_from_public` is enabled. This problem has been patched in the 3.1.1 stable and 3.2.0.beta2 version of Discourse. Users are advised to upgrade. There are no known workarounds for this vulnerability.

Published: 2023-10-16T21:22:24.719Z
Updated: 2024-09-16T15:42:23.929Z

Discourse is an open source platform for community discussion. A malicious request can cause production log files to quickly fill up and thus result in the server running out of disk space. This problem has been patched in the 3.1.1 stable and 3.2.0.beta2 versions of Discourse. It is possible to temporarily work around this problem by reducing the `client_max_body_size nginx directive`. `client_max_body_size` will limit the size of uploads that can be uploaded directly to the server.

Published: 2023-10-16T21:11:26.719Z
Updated: 2024-09-16T15:42:30.893Z

Discourse is an open source platform for community discussion. Attackers with details specific to a poll in a topic can use the `/polls/grouped_poll_results` endpoint to view the content of options in the poll and the number of votes for groups of poll participants. This impacts private polls where the results were intended to only be viewable by authorized users. This issue is patched in the 3.1.1 stable and 3.2.0.beta2 versions of Discourse. There is no workaround for this issue apart from upgrading to the fixed version.

Published: 2023-10-16T21:09:16.620Z
Updated: 2024-09-13T18:59:34.638Z

Discourse is an open source platform for community discussion. Improper escaping of user input allowed for Cross-site Scripting attacks via the digest email preview UI. This issue only affects sites with CSP disabled. This issue has been patched in the 3.1.1 stable release as well as the 3.2.0.beta1 release. Users are advised to upgrade. Users unable to upgrade should ensure CSP is enabled on the forum.

Published: 2023-10-16T21:05:31.991Z
Updated: 2024-09-16T15:51:43.554Z

Discourse is an open-source discussion platform. Prior to version 3.1.1 of the `stable` branch and version 3.2.0.beta1 of the `beta` and `tests-passed` branches, a malicious admin could create extremely large icons sprites, which would then be cached in each server process. This may cause server processes to be killed and lead to downtime. The issue is patched in version 3.1.1 of the `stable` branch and version 3.2.0.beta1 of the `beta` and `tests-passed` branches. This is only a concern for multisite installations. No action is required when the admins are trusted.

Published: 2023-09-15T19:27:59.432Z
Updated: 2024-09-24T18:13:49.117Z

Discourse is an open-source discussion platform. Prior to version 3.1.1 of the `stable` branch and version 3.2.0.beta1 of the `beta` and `tests-passed` branches, importing a remote theme loads their assets into memory without enforcing limits for file size or number of files. The issue is patched in version 3.1.1 of the `stable` branch and version 3.2.0.beta1 of the `beta` and `tests-passed` branches. There are no known workarounds.

Published: 2023-09-15T19:26:43.088Z
Updated: 2024-09-24T18:17:00.835Z

Discourse is an open-source discussion platform. Prior to version 3.1.1 of the `stable` branch and version 3.2.0.beta1 of the `beta` and `tests-passed` branches, a malicious user could add a 2FA or security key with a carefully crafted name to their account and cause a denial of service for other users. The issue is patched in version 3.1.1 of the `stable` branch and version 3.2.0.beta1 of the `beta` and `tests-passed` branches. There are no known workarounds.

Published: 2023-09-15T19:23:39.480Z
Updated: 2024-09-24T18:17:15.320Z

Discourse is an open-source discussion platform. Prior to version 3.1.1 of the `stable` branch and version 3.2.0.beta1 of the `beta` and `tests-passed` branches, a malicious user can create an unlimited number of drafts with very long draft keys which may end up exhausting the resources on the server. The issue is patched in version 3.1.1 of the `stable` branch and version 3.2.0.beta1 of the `beta` and `tests-passed` branches. There are no known workarounds.

Published: 2023-09-15T19:22:08.194Z
Updated: 2024-09-24T18:20:38.265Z

Discourse is an open source discussion platform. Prior to version 3.0.6 of the `stable` branch and version 3.1.0.beta7 of the `beta` and `tests-passed` branches, information about restricted-visibility topic tags could be obtained by unauthorized users. The issue is patched in version 3.0.6 of the `stable` branch and version 3.1.0.beta7 of the `beta` and `tests-passed` branches.

Published: 2023-07-28T15:27:19.780Z
Updated: 2024-10-10T16:01:52.863Z

Discourse is an open source discussion platform. Prior to version 3.0.6 of the `stable` branch and version 3.1.0.beta7 of the `beta` and `tests-passed` branches, in multiple controller actions, Discourse accepts limit params but does not impose any upper bound on the values being accepted. Without an upper bound, the software may allow arbitrary users to generate DB queries which may end up exhausting the resources on the server. The issue is patched in version 3.0.6 of the `stable` branch and version 3.1.0.beta7 of the `beta` and `tests-passed` branches. There are no known workarounds for this vulnerability.

Published: 2023-07-28T15:25:41.132Z
Updated: 2024-10-10T16:03:56.849Z

Discourse is an open source discussion platform. Prior to version 3.0.6 of the `stable` branch and version 3.1.0.beta7 of the `beta` and `tests-passed` branches, a malicious user can prevent the defer queue from proceeding promptly on sites hosted in the same multisite installation. The issue is patched in version 3.0.6 of the `stable` branch and version 3.1.0.beta7 of the `beta` and `tests-passed` branches. There are no known workarounds for this vulnerability. Users of multisite configurations should upgrade.

Published: 2023-07-28T15:18:18.903Z
Updated: 2024-10-10T16:04:31.421Z

Discourse is an open source discussion platform. Prior to version 3.0.6 of the `stable` branch and version 3.1.0.beta7 of the `beta` and `tests-passed` branches, a malicious user can edit a post in a topic and cause a DoS with a carefully crafted edit reason. The issue is patched in version 3.0.6 of the `stable` branch and version 3.1.0.beta7 of the `beta` and `tests-passed` branches. There are no known workarounds for this vulnerability.

Published: 2023-07-28T15:13:46.848Z
Updated: 2024-10-10T16:05:02.743Z

Discourse is an open source discussion platform. Prior to version 3.0.6 of the `stable` branch and version 3.1.0.beta7 of the `beta` and `tests-passed` branches, more users than permitted could be created from invite links. The issue is patched in version 3.0.6 of the `stable` branch and version 3.1.0.beta7 of the `beta` and `tests-passed` branches. As a workaround, use restrict to email address invites.

Published: 2023-07-28T15:09:08.049Z
Updated: 2024-10-10T16:05:21.191Z

Discourse is an open source discussion platform. A CSP (Content Security Policy) nonce reuse vulnerability could allow XSS attacks to bypass CSP protection. There are no known XSS vectors at the moment, but should one be discovered, this vulnerability would allow the XSS attack to completely bypass CSP. The vulnerability is patched in the latest tests-passed, beta and stable branches.

Published: 2023-07-13T20:57:50.880Z
Updated: 2024-10-21T21:09:43.744Z

Discourse is an open source discussion platform. When editing a topic, there is a vulnerability that enables a user to bypass the topic title validations for things like title length, number of emojis in title and blank topic titles. The issue is patched in the latest stable, beta and tests-passed version of Discourse.

Published: 2023-07-14T21:14:01.476Z
Updated: 2024-10-22T13:58:48.183Z

Discourse is an open source discussion platform. Prior to version 3.0.4 of the `stable` branch and version 3.1.0.beta5 of the `beta` and `tests-passed` branches, an attacker could use the new topics dismissal endpoint to reveal the number of topics recently created (but not the actual content thereof) in categories they didn't have access to. This issue is patched in version 3.0.4 of the `stable` branch and version 3.1.0.beta5 of the `beta` and `tests-passed` branches. There are no known workarounds.

Published: 2023-06-13T21:41:29.652Z
Updated: 2025-01-02T21:08:05.472Z

Discourse is an open source discussion platform. Prior to version 3.0.4 of the `stable` branch and version 3.1.0.beta5 of the `beta` and `tests-passed` branches, multiple duplicate topics could be created if topic embedding is enabled. This issue is patched in version 3.0.4 of the `stable` branch and version 3.1.0.beta5 of the `beta` and `tests-passed` branches. As a workaround, disable topic embedding if it has been enabled.

Published: 2023-06-13T21:35:38.188Z
Updated: 2025-01-02T21:05:51.203Z

Discourse is an open source discussion platform. Prior to version 3.0.4 of the `stable` branch and version 3.1.0.beta5 of the `beta` and `tests-passed` branches, the lack of restrictions on the iFrame tag makes it easy for an attacker to exploit the vulnerability and hide subsequent comments from other users. This issue is patched in version 3.0.4 of the `stable` branch and version 3.1.0.beta5 of the `beta` and `tests-passed` branches. There are no known workarounds.

Published: 2023-06-13T21:16:09.257Z
Updated: 2025-01-02T21:04:09.789Z

Discourse is an open source discussion platform. Prior to version 3.0.4 of the `stable` branch and version 3.1.0.beta5 of the `beta` and `tests-passed` branches, if a site has modified their general category permissions, they could be set back to the default. This issue is patched in version 3.0.4 of the `stable` branch and version 3.1.0.beta5 of the `beta` and `tests-passed` branches. A workaround, only if you are modifying the general category permissions, is to use a new category for the same purpose.

Published: 2023-06-13T21:12:47.664Z
Updated: 2025-01-02T21:02:40.153Z

Discourse is an open source platform for community discussion. Due to the improper sanitization of SVG files, an attacker can execute arbitrary JavaScript on the users’ browsers by uploading a crafted SVG file. This issue is patched in the latest stable and tests-passed versions of Discourse. Users are advised to upgrade. For users unable to upgrade there are two possible workarounds: enable CDN handing of uploads (and ensure the CDN sanitizes SVG files) or disable SVG file uploads by ensuring that the `authorized extensions` site setting does not include `svg` (or reset that setting to the default, by default Discourse doesn't enable SVG uploads by users).

Published: 2023-04-18T21:25:58.848Z
Updated: 2025-02-06T16:33:27.722Z

Discourse is an open source platform for community discussion. This vulnerability is not exploitable on the default install of Discourse. A custom feature must be enabled for it to work at all, and the attacker’s payload must pass the CSP to be executed. However, if an attacker succeeds in embedding Javascript that does pass the CSP, it could result in session hijacking for any users that view the attacker’s post. The vulnerability is patched in the latest tests-passed, beta and stable branches. Users are advised to upgrade. Users unable to upgrade should enable and/or restore your site's CSP to the default one provided with Discourse. Remove any embed-able hosts configured.

Published: 2023-04-18T21:24:10.098Z
Updated: 2025-02-06T16:31:16.513Z

Discourse is an open source platform for community discussion. In affected versions a maliciously crafted request from a Discourse administrator can lead to a long-running request and eventual timeout. This has the greatest potential impact in shared hosting environments where admins are untrusted. This issue has been addressed in versions 3.0.3 and 3.1.0.beta4. Users are advised to upgrade. There are no known workarounds for this vulnerability.

Published: 2023-04-18T20:40:13.534Z
Updated: 2025-02-06T16:29:37.700Z

Discourse is an open-source discussion platform. Prior to version 3.1.0.beta3 of the `beta` and `tests-passed` branches, some user provided URLs were being passed to FastImage without SSRF protection. Insufficient protections could enable attackers to trigger outbound network connections from the Discourse server to private IP addresses. This affects any site running the `tests-passed` or `beta` branches versions 3.1.0.beta2 and prior. This issue is patched in version 3.1.0.beta3 of the `beta` and `tests-passed` branches. There are no known workarounds.

Published: 2023-03-17T18:35:07.984Z
Updated: 2025-02-25T14:54:01.690Z

Discourse is an open-source discussion platform. Prior to version 3.0.2 of the `stable` branch and version 3.1.0.beta3 of the `beta` and `tests-passed` branches, a user logged as an administrator can request backups multiple times, which will eat up all the connections to the DB. If this is done on a site using multisite, then it can affect the whole cluster. The vulnerability is patched in version 3.0.2 of the `stable` branch and version 3.1.0.beta3 of the `beta` and `tests-passed` branches. There are no known workarounds.

Published: 2023-03-17T16:23:31.324Z
Updated: 2025-02-25T14:54:15.962Z

Discourse is an open-source discussion platform. Prior to version 3.0.1 of the `stable` branch and version 3.1.0.beta2 of the `beta` and `tests-passed` branches, a maliciously crafted URL can be included in a user's full name field to to carry out cross-site scripting attacks on sites with a disabled or overly permissive CSP (Content Security Policy). Discourse's default CSP prevents this vulnerability. The vulnerability is patched in version 3.0.1 of the `stable` branch and version 3.1.0.beta2 of the `beta` and `tests-passed` branches. As a workaround, enable and/or restore your site's CSP to the default one provided with Discourse.

Published: 2023-03-17T16:07:27.668Z
Updated: 2025-02-25T14:54:25.650Z

Discourse is an open-source messaging platform. In versions 3.0.1 and prior on the `stable` branch and versions 3.1.0.beta2 and prior on the `beta` and `tests-passed` branches, the count of personal messages displayed for a tag is a count of all personal messages regardless of whether the personal message is visible to a given user. As a result, any users can technically poll a sensitive tag to determine if a new personal message is created even if the user does not have access to the personal message. In the patched versions, the count of personal messages tagged with a given tag is hidden by default. To revert to the old behaviour of displaying the count of personal messages for a given tag, an admin may enable the `display_personal_messages_tag_counts` site setting.

Published: 2023-03-16T20:21:13.539Z
Updated: 2025-02-25T14:54:52.894Z

Discourse is an open-source discussion platform. Prior to version 3.0.1 on the `stable` branch and version 3.1.0.beta2 on the `beta` and `tests-passed` branches, someone can use the `exclude_tag param` to filter out topics and deduce which ones were using a specific hidden tag. This affects any Discourse site using hidden tags in public categories. This issue is patched in version 3.0.1 on the `stable` branch and version 3.1.0.beta2 on the `beta` and `tests-passed` branches. As a workaround, secure any categories that are using hidden tags, change any existing hidden tags to not include private data, or remove any hidden tags currently in use.

Published: 2023-01-27T23:35:10.242Z
Updated: 2025-03-10T21:17:55.270Z

Discourse is an open-source discussion platform. Prior to version 3.0.1 of the `stable` branch and version 3.1.0.beta2 of the `beta` and `tests-passed` branches, the count of topics displayed for a tag is a count of all regular topics regardless of whether the topic is in a read restricted category or not. As a result, any users can technically poll a sensitive tag to determine if a new topic is created in a category which the user does not have excess to. In version 3.0.1 of the `stable` branch and version 3.1.0.beta2 of the `beta` and `tests-passed` branches, the count of topics displayed for a tag defaults to only counting regular topics which are not in read restricted categories. Staff users will continue to see a count of all topics regardless of the topic's category read restrictions.

Published: 2023-03-17T14:17:17.427Z
Updated: 2025-02-25T14:54:38.172Z

Discourse is an open-source discussion platform. Prior to version 3.0.1 on the `stable` branch and version 3.1.0.beta2 on the `beta` and `tests-passed` branches, a malicious user can cause a regular expression denial of service using a carefully crafted user agent. This issue is patched in version 3.0.1 on the `stable` branch and version 3.1.0.beta2 on the `beta` and `tests-passed` branches. There are no known workarounds.

Published: 2023-01-27T23:31:05.923Z
Updated: 2025-03-10T21:18:01.772Z

Discourse is an open-source discussion platform. Prior to version 3.0.1 on the `stable` branch and 3.1.0.beta2 on the `beta` and `tests-passed` branches, the contents of latest/top routes for restricted tags can be accessed by unauthorized users. This issue is patched in version 3.0.1 on the `stable` branch and 3.1.0.beta2 on the `beta` and `tests-passed` branches. There are no known workarounds.

Published: 2023-01-27T00:00:00.000Z
Updated: 2025-03-10T21:19:00.947Z

Discourse is an open-source discussion platform. Prior to version 3.0.1 on the `stable` branch and 3.1.0.beta2 on the `beta` and `tests-passed` branches, when submitting a membership request, there is no character limit for the reason provided with the request. This could potentially allow a user to flood the database with a large amount of data. However it is unlikely this could be used as part of a DoS attack, as the paths reading back the reasons are only available to administrators. Starting in version 3.0.1 on the `stable` branch and 3.1.0.beta2 on the `beta` and `tests-passed` branches, a limit of 280 characters has been introduced for membership requests.

Published: 2023-01-27T00:00:00.000Z
Updated: 2025-03-10T21:19:07.953Z

Discourse is an open source discussion platform. The embeddable comments can be exploited to create new topics as any user but without any clear title or content. This issue is patched in the latest stable, beta and tests-passed versions of Discourse. As a workaround, disable embeddable comments by deleting all embeddable hosts.

Published: 2023-02-03T21:57:29.878Z
Updated: 2025-03-10T21:16:16.563Z

Discourse is an option source discussion platform. Prior to version 2.8.14 on the `stable` branch and version 3.0.0.beta16 on the `beta` and `tests-passed` branches, tag descriptions, which can be updated by moderators, can be used for cross-site scripting attacks. This vulnerability can lead to a full XSS on sites which have modified or disabled Discourse’s default Content Security Policy. Versions 2.8.14 and 3.0.0.beta16 contain a patch.

Published: 2023-01-05T20:02:40.608Z
Updated: 2025-03-10T21:31:40.480Z

Discourse is an option source discussion platform. Prior to version 2.8.14 on the `stable` branch and version 3.0.0.beta16 on the `beta` and `tests-passed` branches, pending post titles can be used for cross-site scripting attacks. Pending posts can be created by unprivileged users when a category has the "require moderator approval of all new topics" setting set. This vulnerability can lead to a full XSS on sites which have modified or disabled Discourse’s default Content Security Policy. A patch is available in versions 2.8.14 and 3.0.0.beta16.

Published: 2023-01-05T19:58:36.355Z
Updated: 2025-03-10T21:31:46.858Z

Discourse is an option source discussion platform. Prior to version 2.8.14 on the `stable` branch and version 3.0.0.beta16 on the `beta` and `tests-passed` branches, the number of times a user posted in an arbitrary topic is exposed to unauthorized users through the `/u/username.json` endpoint. The issue is patched in version 2.8.14 and 3.0.0.beta16. There is no known workaround.

Published: 2023-01-05T19:53:34.180Z
Updated: 2025-03-10T21:31:52.286Z

Discourse is an option source discussion platform. Prior to version 2.8.14 on the `stable` branch and version 3.0.0.beta16 on the `beta` and `tests-passed` branches, when a user requests for a password reset link email, then changes their primary email, the old reset email is still valid. When the old reset email is used to reset the password, the Discourse account's primary email would be re-linked to the old email. If the old email address is compromised or has transferred ownership, this leads to an account takeover. This is however mitigated by the SiteSetting `email_token_valid_hours` which is currently 48 hours. Users should upgrade to versions 2.8.14 or 3.0.0.beta15 to receive a patch. As a workaround, lower `email_token_valid_hours ` as needed.

Published: 2023-01-05T19:48:05.483Z
Updated: 2025-03-10T21:31:57.876Z