Desktop

Zen is a firefox-based browser. Prior to 1.21.5b, Zen's glance and split-view context-menu actions, Open link in glance and Split link in new tab, load a page-controlled link URL with the System principal instead of the originating page's principal, allowing a malicious web page to place a link to a file URL that can load with System privileges when opened through either context-menu item and bypass the content-to-file security check that blocks an ordinary click. This issue is fixed in version 1.21.5b.

Published: 2026-07-09T22:27:34.962Z
Updated: 2026-07-10T20:59:23.914Z

Zen is a firefox-based browser. Prior to 1.19.13b, Zen Browser did not provide a persistent, clearly visible security notification when a webpage entered fullscreen mode, allowing an attacker-controlled page to hide the real browser UI and origin information, imitate a trusted website UI, and combine with long-domain URL eliding to spoof a trusted origin for phishing and credential theft. This issue is fixed in version 1.19.13b.

Published: 2026-07-15T15:35:17.010Z
Updated: 2026-07-15T17:44:16.341Z

Zen is a firefox-based browser. Prior to 1.19.12b, the ZEN Browser incorrectly truncates long hostnames in the address bar and shows only the attacker-controlled prefix of the subdomain, hiding the actual registrable domain (eTLD+1). As a result, an attacker can craft extremely long malicious subdomains that visually imitate trusted brands, and the browser will display only the spoofed prefix, misleading users about the actual origin of the site. This directly compromises the URL bar as a security indicator and creates a phishing/supply-chain attack vector. This vulnerability is fixed in 1.19.12b.

Published: 2026-05-11T17:01:18.559Z
Updated: 2026-05-12T16:13:51.896Z

Zen is a firefox-based browser. Prior to 1.19.12b, RSS feed URLs entered by the user are validated to http: or https: in promptForFeedUrl, but item links inside the feed are not subject to the same restriction. The provider maps each RSS/Atom item link into item.url, filters only for presence and date, and returns the item list. The live-folder manager later creates pinned lazy tabs from these values with gBrowser.addTrustedTab(item.url, ...). This vulnerability is fixed in 1.19.12b.

Published: 2026-05-11T17:00:31.639Z
Updated: 2026-05-11T19:04:14.434Z

Zen is a firefox-based browser. Prior to 1.19.9b, Zen Browser ships a Mozilla Application Resource (MAR) updater (org.mozilla.updater) that has had all MAR signature verification stripped from the Firefox codebase it was forked from. The MAR files served to users contain zero cryptographic signatures, and the updater binary contains zero cryptographic verification code. This eliminates the defense-in-depth that MAR signing provides. If the update server or GitHub release pipeline is compromised, arbitrary unsigned code can be delivered to all Zen users via the auto-update mechanism. This vulnerability is fixed in 1.19.9b.

Published: 2026-05-11T16:55:10.814Z
Updated: 2026-05-11T18:31:38.146Z