Apache Storm Client

Description `SimpleACLAuthorizer` evaluated the user-level command set by returning early when `nimbus.users` was empty, before `nimbus.groups` was considered. An operator who restricted cluster access by group alone, leaving `nimbus.users` unset, therefore received no restriction at all: every authenticated principal was permitted every user-level operation, including `submitTopology`, `beginFileUpload` and `getNimbusConf`. `docs/SECURITY.md` presents `nimbus.groups` as a supported way to lock down a cluster, so a deployment following the documentation could believe it was restricted while it was not. The failure is silent; nothing in the logs or the configuration indicates that the group list is being ignored. Both lists left empty continues to mean that no restriction is configured, which is the shipped default and is unchanged. Mitigation Upgrade to 3.1.0, where `nimbus.groups` is evaluated whether or not `nimbus.users` is set. Users who cannot upgrade immediately should additionally populate `nimbus.users` with the intended principals, since a non-empty user list causes the group list to be evaluated on affected versions. Operators should review Nimbus access logs for operations by principals outside the intended groups. Note that after upgrading, a cluster configured with `nimbus.groups` alone becomes restrictive for the first time. This includes `NimbusClient`, which calls `getLeader` on every connection, so clients outside the configured groups will begin to be refused. Credit The ASF -- found using Claude agents to study the security of open-source projects, validated and reported by Apache Storm.

Published: 2026-09-14T14:14:48.439Z
Updated: 2026-09-14T20:01:54.073Z

Description Dependency artifacts uploaded with `storm jar --artifacts` were stored under a blob key derived only from the Maven coordinate, for example `dep---.jar`. The key was therefore identical for every user of the cluster and predictable in advance. When the blob already existed, the uploader caught `KeyAlreadyExistsException` and silently reused it, with no check that the existing blob's content or owner matched the artifact the submitter had resolved. A user who uploaded a blob under such a key first therefore controlled the bytes that every later submitter of the same coordinate would receive on the worker classpath, resulting in code execution inside another tenant's topology. This affects deployments where more than one principal may create blobs and where the `--artifacts` dependency feature is used. Mitigation Upgrade to 3.1.0, where each uploaded artifact receives a key carrying a freshly generated UUID and a pre-existing blob is no longer silently reused. Note that the corrected key generation is on the SUBMITTING CLIENT, so upgrading the cluster alone does not close this; every client that runs `storm jar --artifacts` must also be upgraded. Operators should audit existing `dep-` blobs for unexpected owners before upgrading. Users who cannot upgrade immediately should avoid the `--artifacts` mechanism in multi-tenant clusters and distribute dependencies inside the topology jar instead. Credit The ASF -- found using Claude agents to study the security of open-source projects, validated and reported by Apache Storm.

Published: 2026-09-14T14:18:09.921Z
Updated: 2026-09-14T19:59:04.884Z

Description When ZooKeeper authentication is configured, Storm deliberately retains `storm.zookeeper.topology.auth.payload` in the topology configuration, because workers need it. Nimbus then served that configuration verbatim to any caller holding read-only topology permissions, so a user whose only grant was the ability to view a topology received its ZooKeeper credential. That credential is not read-only. The cluster state implementation uses write-capable ACLs for worker heartbeats, backpressure and error state, so a recipient can forge or remove that state for the topology concerned. It is not a write credential on assignments. The same advisory covers the submission client, which logged the generated payload at INFO on every submission that generated one, and the SASL handlers, which logged it at DEBUG. The credential therefore also reached any log aggregation or support bundle collected from the cluster. Mitigation Upgrade to 3.1.0, where the payload is removed from the configuration served to read-only callers and is no longer written to logs. Users who cannot upgrade immediately should rotate `storm.zookeeper.topology.auth.payload` for existing topologies, review retained logs and support bundles for the value, and restrict read-only topology permissions to trusted principals. Credit The ASF -- found using Claude agents to study the security of open-source projects, validated and reported by Apache Storm.

Published: 2026-09-14T14:10:15.326Z
Updated: 2026-09-14T19:50:34.074Z

Improper Handling of TLS Client Authentication Failure Leading to Anonymous Principal Assignment in Apache Storm Versions Affected: up to 2.8.7 Description: When TLS transport is enabled in Apache Storm without requiring client certificate authentication (the default configuration), the TlsTransportPlugin assigns a fallback principal (CN=ANONYMOUS) if no client certificate is presented or if certificate verification fails. The underlying SSLPeerUnverifiedException is caught and suppressed rather than rejecting the connection. This fail-open behavior means an unauthenticated client can establish a TLS connection and receive a valid principal identity. If the configured authorizer (e.g., SimpleACLAuthorizer) does not explicitly deny access to CN=ANONYMOUS, this may result in unauthorized access to Storm services. The condition is logged at debug level only, reducing visibility in production. Impact: Unauthenticated clients may be assigned a principal identity, potentially bypassing authorization in permissive or misconfigured environments. Mitigation: Users should upgrade to 2.8.7 in which TLS authentication failures are handled in a fail-closed manner. Users who cannot upgrade immediately should: - Enable mandatory client certificate authentication (nimbus.thrift.tls.client.auth.required: true) - Ensure authorization rules explicitly deny access to CN=ANONYMOUS - Review all ACL configurations for implicit default-allow behavior

Published: 2026-04-27T13:10:45.886Z
Updated: 2026-04-27T14:43:31.605Z

Deserialization of Untrusted Data vulnerability in Apache Storm. Versions Affected: before 2.8.6. Description: When processing topology credentials submitted via the Nimbus Thrift API, Storm deserializes the base64-encoded TGT blob using ObjectInputStream.readObject() without any class filtering or validation. An authenticated user with topology submission rights could supply a crafted serialized object in the "TGT" credential field, leading to remote code execution in both the Nimbus and Worker JVMs. Mitigation: 2.x users should upgrade to 2.8.6. Users who cannot upgrade immediately should monkey-patch an ObjectInputFilter allow-list to ClientAuthUtils.deserializeKerberosTicket() restricting deserialized classes to javax.security.auth.kerberos.KerberosTicket and its known dependencies. A guide on how to do this is available in the release notes of 2.8.6. Credit: This issue was discovered by K.

Published: 2026-04-13T09:11:06.193Z
Updated: 2026-04-14T03:55:31.489Z