CVE-2026-11642: Chrome Use-After-Free Sandbox Escape (149.0.7827.103)

Technical summary

This vulnerability is a use-after-free condition (CWE-416) occurring in Chrome's web apps subsystem. Use-after-free flaws arise when a program continues to reference memory after it has been freed, allowing attackers to read sensitive data or execute arbitrary code. In this case, the flaw exists in a code path that processes web application content, and successful exploitation requires two preconditions: prior compromise of the Chrome renderer process and user interaction with a specially crafted HTML page. The vulnerability permits a sandbox escape—breaking out of the restricted execution environment that normally isolates the browser from the underlying operating system. Chromium's security team classified this as Critical severity due to the sandbox escape potential.

Business impact

Successful exploitation could result in complete system compromise. An attacker who chains this vulnerability with a prior renderer process vulnerability could gain full control of an affected machine, leading to data theft, malware installation, lateral movement within networks, or ransomware deployment. For organizations, this poses a particularly acute risk if employees use Chrome in high-security roles or handle sensitive data. The requirement for renderer compromise and user interaction reduces immediate risk from mass exploitation, but determined adversaries targeting specific users or organizations could weaponize this effectively.

Affected systems

Google Chrome versions prior to 149.0.7827.103 running on Windows, macOS, and Linux are directly affected. The vulnerability is platform-independent once Chrome is deployed, meaning all three operating systems face equal risk. Organizations should audit Chrome deployment across all endpoints regardless of OS. While the underlying vulnerability is in Chromium (the open-source base), users of Chrome derivatives or embedded Chromium instances should verify their vendor's patching status independently.

Exploitability

The CVSS 3.1 score of 8.3 (HIGH) reflects a high-severity but not trivially exploitable vulnerability. The attack vector is network-based, but the attack complexity is rated High because it requires the renderer process to be compromised first—meaning this is not a one-step attack. Additionally, the vulnerability requires user interaction (clicking a link, visiting a site). The impact is severe (confidentiality, integrity, and availability all affected), and the scope changes, meaning the vulnerability can affect resources beyond the vulnerable component. The barrier to weaponization is the prerequisite renderer compromise; however, browser exploits are routinely chained together in real-world campaigns, making the practical risk higher than the base score alone suggests.

Remediation

Update Google Chrome to version 149.0.7827.103 or later immediately. Chrome's auto-update mechanism should deliver this patch automatically on most deployments, but verify completion via chrome://version in the address bar. For organizations managing Chrome at scale, use enterprise deployment tools to push updates and verify compliance. No workarounds exist short of disabling Chrome or restricting web access; patching is the only remediation. If a renderer vulnerability is suspected to have been exploited on a system, assume potential compromise and conduct forensic investigation before applying this patch.

Patch guidance

Verify successful patching by navigating to chrome://version and confirming the version string displays 149.0.7827.103 or higher. For managed deployments, configure enterprise policies to enforce automatic updates and prevent version rollback. Test patching in a non-critical environment first to rule out compatibility issues with internal web applications, though Chrome's patch history shows rare breakage at this version level. Once deployed, monitor for any unusual browser behavior or unexpected outbound connections that might indicate prior exploitation. If your organization runs Chrome OS, updates are automatic; traditional OS deployments may require group policy or endpoint management platform enforcement.

Detection guidance

Monitor for Chrome crashes or restart cycles immediately after the vulnerability disclosure date, as attackers may induce visible failures while probing systems. Web application firewalls should scrutinize HTML pages for unusual structures or references that might trigger the use-after-free condition, though signature-based detection is difficult without vendor indicators. Monitor process execution logs for child processes spawned by Chrome with unexpected privileges or system calls indicative of sandbox escape attempts. Endpoint Detection and Response (EDR) platforms should flag Chrome spawning system binaries or accessing protected kernel structures. Given the requirement for renderer compromise, network detection should also focus on identifying any prior Chromium/browser vulnerabilities being exploited in your environment.

Why prioritize this

Despite the CVSS score of 8.3 and the sandbox-escape capability, this vulnerability should be prioritized as URGENT but not necessarily above all other critical issues, because it requires a pre-existing renderer compromise. However, because browser exploits are commonly chained and widely used by sophisticated threat actors, assume this will be combined with other exploits in real campaigns. Organizations with high-risk user populations (finance, government, research) or those processing sensitive data in browsers should treat this as an immediate patch target. The public disclosure and Chromium severity designation create time pressure; actors will begin weaponizing this quickly once detailed technical information emerges.

Risk score, explained

The CVSS 3.1 score of 8.3 (HIGH) is driven by: (1) Network attack vector—remotely triggerable; (2) High attack complexity—requires prior renderer compromise and user interaction; (3) No privilege requirement for the attacker; (4) Required user interaction (clicking/visiting a site); (5) Scope change (impacts beyond the web app itself); (6) High confidentiality, integrity, and availability impact (system-level compromise possible). The score reflects that this is a serious vulnerability but not automatically exploitable in isolation. Real-world risk is elevated by the chaining potential with other browser exploits and the ubiquity of Chrome in enterprise environments.

Frequently asked questions