CVE-2026-13029: Chrome Web Authentication Use-After-Free Vulnerability

Technical summary

CVE-2026-13029 is a use-after-free vulnerability (CWE-416) in the Web Authentication subsystem of Google Chrome versions before 149.0.7827.197. The flaw arises when memory references are accessed after being freed, creating a heap corruption condition. A threat actor must first socially engineer a user into installing a malicious extension, then use that extension to trigger the use-after-free through crafted Web Authentication API calls or similar mechanisms. The Chromium security team rated this High severity due to the potential for memory corruption and the broad consequences for browser integrity.

Business impact

For organizations, this vulnerability threatens user data confidentiality and browser integrity. Users operating Chrome on managed systems could become vectors for data theft or lateral movement if an attacker gains code execution. The social engineering prerequisite—convincing users to install extensions—does place practical limits on widespread exploitation, but targeted campaigns against high-value users or organizations with lax extension governance could succeed. Incident response teams should monitor for anomalous extension installations and unusual browser behavior.

Affected systems

Google Chrome on Windows, macOS, and Linux systems running versions prior to 149.0.7827.197 are vulnerable. While the vulnerability is technically in Chromium (the open-source foundation), the CVE applies specifically to Chrome; other Chromium derivatives may inherit the risk depending on their patch cadence. Organizations should verify their Chrome deployment version and auto-update configuration.

Exploitability

Exploitation is not trivial but remains practical for motivated attackers. The attack requires convincing a user to install a malicious extension—a social engineering hurdle—plus a correctly crafted extension that triggers the heap corruption. The CVSS vector (AC:H) reflects this elevated attack complexity. No public proof-of-concept or in-the-wild exploitation has been disclosed as of publication, though active attackers will likely develop working exploits once patch details become widely understood. Users with strong browser extension governance and security awareness training represent lower risk.

Remediation

Update Google Chrome to version 149.0.7827.197 or later immediately. Chrome's auto-update mechanism should deliver this patch automatically to most users, but corporate deployments using managed Chrome policies should verify rollout. Additionally, audit and remove any suspicious or unnecessary extensions from user machines; restrict extension installation via enterprise policy where feasible to reduce the social engineering surface.

Patch guidance

Google Chrome users on all supported platforms (Windows, macOS, Linux) should upgrade to 149.0.7827.197 or above. Verify the current version by navigating to chrome://settings/help; Chrome will auto-update if enabled. In enterprise environments, administrators can check the Chrome Version History to confirm patch deployment. If auto-update is disabled, manually trigger updates through the settings menu or enforce the update via mobile device management or Group Policy. No configuration workarounds mitigate this flaw; patching is the primary remedy.

Detection guidance

Monitor for suspicious Chrome extension installations, especially from untrusted sources or installed without user consent. Endpoint Detection and Response (EDR) tools should flag unusual Chrome process behavior such as heap corruption crashes, unexpected memory access patterns, or spawned child processes. Log and review extension permissions requests, particularly those requesting broad host access or Web Authentication API interaction. Network detection could identify communication from compromised Chrome instances to attacker-controlled servers post-exploitation.

Why prioritize this

This vulnerability should be prioritized due to its HIGH CVSS score (7.5), high impact on confidentiality and integrity, and the potential for code execution within the browser sandbox. Although the attack complexity is elevated (requiring social engineering and a crafted extension), the consequences—memory corruption, potential RCE, and data theft—are severe. The lack of current public exploitation and KEV status provides a narrow window for proactive patching before adversaries weaponize the flaw at scale.

Risk score, explained

The CVSS 3.1 score of 7.5 (HIGH) reflects a high-impact vulnerability with moderate exploitability barriers. The attack vector is network-based (AV:N), but attack complexity is high (AC:H) due to the social engineering and extension crafting requirements. User interaction is required (UI:R). The scope is unchanged (S:U), meaning the vulnerability is confined to the Chrome process. Confidentiality, Integrity, and Availability impacts are all rated High (C:H/I:H/A:H) because successful exploitation enables arbitrary code execution. The score appropriately balances the severe consequences against the practical obstacles to exploitation.

Frequently asked questions