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Google fixed CVE-2026-95301, a high-severity Chromium Site Isolation bypass in the extensions accessibility-automation infrastructure. A compromised, site-locked web renderer could bind the previously unprotected RendererAutomationRegistry interface and register a rogue automation receiver without browser-side authorization.
If a legitimate chrome.automation consumer was active, the rogue receiver could obtain serialized accessibility-tree data from other origins and tabs, including visible page text, non-password form values, ARIA content, and cross-site frame URLs; the flaw also had potential cross-profile and Incognito exposure. Chromium now verifies that the calling renderer hosts an enabled extension with automation permission and terminates unauthorized renderers; the fix was targeted for Chrome M154 release notes.
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5 events from the most recent confirmed update back to the earliest known activity.
A vulnerability in Chromium's accessibility-automation infrastructure was reported to the Chrome Vulnerability Reward Program. A compromised site-locked renderer could register an unauthorized automation receiver and obtain cross-origin accessibility-tree data when a legitimate chrome.automation consumer was active.
Chromium registered CVE-2026-95301 for the accessibility-automation Site Isolation bypass and targeted vulnerability release notes for Chrome M154.
Chromium removed access restrictions from the vulnerability issue after it had been closed for more than 30 days.
The Chrome Vulnerability Reward Program awarded the reporter $5,000 and characterized the flaw as a Site Isolation bypass with preconditions.
Chromium fixed the RendererAutomationRegistry authorization flaw by adding ProcessMap and AutomationInfo checks in AutomationEventRouter::BindForRenderer. Unauthorized renderer processes were changed to receive a bad message and be terminated; backports were requested for Chrome M150 through M153.
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Chromium fixed **CVE-2026-95344**, a Chrome DevTools vulnerability that could let a malicious extension execute JavaScript inside another extension's content-script isolated world. The attack combined a time-of-check/time-of-use flaw in DevTools keyboard-shortcut forwarding with insufficient authorization for evaluation in a debugger-selected call frame. An attacker could pause execution, select a victim extension's frame, and invoke victim-scoped APIs, including `chrome.storage.local`; the issue was demonstrated against MetaMask. Chromium's DevTools frontend changes validate forwarded shortcuts and block ExtensionServer evaluation while paused, with release notes planned for Chrome M154.
Sep 23, 2026
A serious unpatched **Chromium** vulnerability was accidentally exposed after Google engineers marked the issue as fixed without shipping a patch, causing the bug report and proof-of-concept to become public. The flaw, originally reported in 2022, abuses the **Background Fetch API** to keep a Service Worker and malicious JavaScript running after the browser is closed and, in some cases, even after a device reboot. Affected products include **Chrome**, **Microsoft Edge**, **Brave**, **Opera**, **Vivaldi**, and **Arc**. The bug could let attackers abuse victims’ browsers for proxying traffic, launching DDoS activity, opening websites, and tracking user behavior; Google later re-hid the report and said it is working on a fix. Separately, researchers analyzing the **VoidStealer** infostealer found it can bypass Chrome’s **Application-Bound Encryption (ABE)** on Windows by attaching to the browser as a debugger, intercepting the moment Chrome decrypts protected data, and extracting the master key from memory. That technique enables theft of cookies, sessions, and other sensitive browser data, and the risk extends to other Chromium-based browsers using the same protection model. Together, the disclosures show that Chromium ecosystems face both browser-level persistence abuse and post-compromise data theft, with defenders urged to watch for unusual download-menu behavior, keep browsers updated as fixes arrive, and harden endpoints against infostealer activity.
Jun 29, 2026
Google’s **Site Isolation** architecture was designed to limit the impact of renderer compromise by placing different sites into separate sandboxed processes and preventing most cross-site data from reaching the wrong renderer. The defense was rolled out broadly across desktop Chrome and later expanded to cover additional scenarios including compromised renderers, extension isolation, and selected Android use cases, adding protection beyond the Same Origin Policy and Chrome’s existing sandbox against threats such as **UXSS** and side-channel attacks including **Spectre**. Researchers later showed that a browser-process use-after-free in Chrome’s `InstalledAppProvider` Mojo interface, tracked as **Issue 1062091**, could let an attacker with a compromised renderer escape that sandbox entirely. The flaw stemmed from a stale `RenderFrameHost` pointer retained after destruction, and the published exploit demonstrated a reliable path to browser-process code execution and an unsandboxed renderer by appending `--no-sandbox` to Chrome’s command line; Chromium-based Microsoft Edge was also affected, and the bug was reachable on desktop systems in **Chrome Stable 81** before being moved behind an experimental flag in Chrome 82.
Jul 24, 2026