CVE-2026-11640: Google Chrome RCE Vulnerability

CVE-2026-11640 Overview

CVE-2026-11640 is an integer overflow vulnerability in the libyuv library used by Google Chrome versions prior to 149.0.7827.103. The flaw allows a remote attacker who has already compromised the renderer process to potentially escape the Chrome sandbox using a crafted HTML page. Chromium engineers rated the security severity as Critical. The vulnerability is tracked under [CWE-472] and impacts Chrome installations on Windows, macOS, and Linux. Exploitation requires user interaction and chains with a prior renderer compromise, which limits opportunistic abuse but raises the impact for targeted attacks.

Critical Impact

Successful exploitation enables a sandbox escape from a compromised renderer, giving attackers code execution at the broader browser process privilege level.

Affected Products

• Google Chrome prior to 149.0.7827.103
• Apple macOS (Chrome desktop builds)
• Microsoft Windows and Linux (Chrome desktop builds)

Discovery Timeline

• 2026-06-09 - CVE-2026-11640 published to NVD
• 2026-06-09 - Google releases Chrome Stable channel update addressing the issue
• 2026-06-09 - Last updated in NVD database

Technical Details for CVE-2026-11640

Vulnerability Analysis

The vulnerability resides in libyuv, an open-source library Chromium uses for YUV color space scaling and conversion. An integer overflow occurs when crafted input causes arithmetic on image dimensions or buffer size calculations to wrap around expected bounds. The undersized allocation that follows produces an out-of-bounds memory access in a privileged Chromium process.

Because libyuv operates outside the renderer sandbox during certain media pipeline operations, the overflow becomes a viable pivot point for sandbox escape. An attacker who already controls the renderer process can deliver malformed image or video data through the standard inter-process channels and trigger the flaw in the browser or GPU process context.

Root Cause

The root cause is an external control of an assumed-immutable size value [CWE-472] feeding arithmetic operations in libyuv without sufficient bounds validation. When width, height, or stride values multiply past the maximum representable integer, the result wraps, and downstream allocation or indexing operates on a corrupted size.

Attack Vector

Exploitation is a two-stage chain. The attacker first lures the victim to a crafted HTML page that compromises the renderer through a separate primitive. The attacker then uses the renderer foothold to submit malformed image dimensions to libyuv and trigger the overflow in the targeted Chromium process. The CVSS vector reflects high attack complexity and required user interaction, consistent with the chained exploitation model.

Verified proof-of-concept code is not publicly available. See the Chromium Issue Tracker Entry for any disclosed technical details once restrictions are lifted.

Detection Methods for CVE-2026-11640

Indicators of Compromise

• Chrome browser or GPU process crashes correlated with media or image decoding activity, especially with libyuv frames on the stack.
• Unexpected child process spawns from chrome.exe following visits to untrusted pages.
• Outbound connections from Chrome helper processes to non-standard hosts shortly after rendering attacker-controlled content.

Detection Strategies

• Monitor endpoint telemetry for Chrome process anomalies, including unsigned module loads and atypical memory regions marked executable inside browser child processes.
• Hunt for browser exploitation patterns where a renderer process is followed by privileged file system or registry writes outside the Chrome profile directory.
• Correlate web proxy logs with EDR telemetry to identify users who visited pages immediately before browser process instability.

Monitoring Recommendations

• Track installed Chrome versions across the fleet and alert on hosts running builds older than 149.0.7827.103.
• Enable crash reporting aggregation and review crashes referencing libyuv symbols.
• Apply browser isolation or strict content policies for high-risk user groups handling sensitive data.

How to Mitigate CVE-2026-11640

Immediate Actions Required

• Update Google Chrome to version 149.0.7827.103 or later on Windows, macOS, and Linux endpoints.
• Restart Chrome after the update so the patched binaries replace the in-memory components.
• Audit managed deployments to confirm auto-update is functioning and not blocked by group policy or network controls.

Patch Information

Google addressed CVE-2026-11640 in the Chrome Stable channel update referenced in the Google Chrome Stable Update advisory. Chromium-based browsers that embed libyuv should consume the upstream fix from the Chromium Issue Tracker Entry and ship corresponding updates.

Workarounds

• No vendor-supplied workaround exists; patching is the only complete remediation.
• Restrict browsing to trusted sites through enterprise allowlists until updates are deployed.
• Deploy Chrome enterprise policies that disable unnecessary media features for high-risk user groups as a temporary risk reduction.

# Verify Chrome version on Linux endpoints
google-chrome --version

# Force update check via Chrome admin URL
# Navigate to: chrome://settings/help