CVE-2026-9978: Chrome Use-After-Free Vulnerability in Glic Component

Technical summary

CVE-2026-9978 is a use-after-free vulnerability (CWE-416) in the Glic component of Chromium/Google Chrome. The flaw occurs when freed memory is accessed after deallocation, allowing a remote attacker to corrupt the heap and execute arbitrary code within the browser sandbox. The vulnerability requires user interaction—a victim must visit or be redirected to a crafted HTML page—but no authentication or special privileges are needed. Google assigned this a High security severity rating, and the CVSS 3.1 score of 8.8 reflects the high impact on confidentiality, integrity, and availability within the sandbox context.

Business impact

Successful exploitation could expose sensitive user data—passwords, session tokens, personal information, and intellectual property—cached or in-transit within the browser. Organizations relying on web-based applications face increased risk of credential theft and account compromise. The sandbox containment limits direct OS-level damage, but attackers may chain this vulnerability with other flaws to escape the sandbox. Unpatched deployments represent a material risk to user privacy and organizational data security, particularly in environments handling sensitive customer or proprietary information.

Affected systems

This vulnerability affects Google Chrome on Windows, macOS, and Linux systems running versions prior to 148.0.7778.216. The vulnerability does not appear to affect Chromium-based browsers built from unpatched source code or derivative products that have not integrated the fix. Enterprise environments with Chrome as a standard browser—especially those using managed deployments—should prioritize patching across all affected platforms.

Exploitability

The attack vector is network-based and requires no special privileges, but user interaction is mandatory; the victim must open a malicious HTML page, typically through social engineering, phishing, or drive-by download tactics. The exploit does not require knowledge of memory layout randomization (ASLR), making it moderately reliable in practice. No public exploit or active in-the-wild campaign targeting this vulnerability has been reported as of the last update, but the low barrier to user interaction and the high impact make this a credible threat if attackers discover it.

Remediation

Update Google Chrome to version 148.0.7778.216 or later immediately. Both manual updates (Settings > About Chrome) and managed enterprise deployments via group policy or mobile device management should be prioritized. Users should enable automatic updates if not already configured. No known workarounds mitigate the vulnerability; patching is the only reliable remediation.

Patch guidance

Google Chrome auto-updates are enabled by default and will roll out version 148.0.7778.216 to users over time. Enterprise administrators should force immediate deployment through management tools rather than relying on gradual rollout. Verify the update version in Chrome settings (chrome://settings/help) displays 148.0.7778.216 or higher. Test the patch in a staging environment before broad deployment to ensure compatibility with internal web applications and extensions. Users on macOS and Linux should check system updates, as Chrome may be bundled with OS-level security updates.

Detection guidance

Monitor Chrome version inventory across your environment using endpoint detection and response (EDR) tools, mobile device management (MDM) for personal devices, or browser telemetry. Flag any systems running versions below 148.0.7778.216. Log and analyze failed or successful exploitation attempts through browser crash logs, sandbox exit events, and unexpected child process spawning from Chrome. Network-based detection is limited; focus on endpoint telemetry and user reports of browser crashes or unusual behavior after visiting untrusted links. Educate users to report suspicious pages or unexpected browser crashes promptly.

Why prioritize this

The combination of high CVSS score (8.8), remote network exploitability, user-interaction requirement, and potential for data exfiltration warrants prompt patching within 7–14 days for most organizations. While the sandbox containment provides defense-in-depth, the lack of public active exploitation and lower complexity of the exploit itself make this a high-priority but not emergency patch. Prioritize systems used by high-value targets (executives, developers, finance staff) and public-facing kiosks or shared devices.

Risk score, explained

The CVSS 3.1 score of 8.8 (HIGH) reflects: (1) network-accessible attack surface (AV:N); (2) low complexity exploitation requiring no special conditions (AC:L); (3) no privileges required (PR:N); (4) mandatory user interaction (UI:R), slightly reducing severity; (5) no scope change (S:U), meaning impact is limited to the browser sandbox; and (6) high impact on confidentiality, integrity, and availability within that scope (C:H, I:H, A:H). The sandbox containment and user-interaction requirement prevent a Critical rating, but the ease of delivery via web content and potential for sensitive data theft justify the HIGH classification.

Frequently asked questions