CVE-2026-9926: Chrome ANGLE Heap Buffer Overflow Sandbox Escape

Technical summary

CVE-2026-9926 is a heap buffer overflow (CWE-122) in the ANGLE graphics library used by Google Chrome. The vulnerability exists in Chrome versions before 148.0.7778.216 and can be exploited by a remote attacker who has already achieved code execution in the renderer process. By sending a malicious HTML page, the attacker can trigger memory corruption that breaks renderer sandbox isolation, potentially allowing privilege escalation or system access. The CVSS 3.1 score of 8.3 (High severity) reflects the high impact on confidentiality, integrity, and availability, though exploitation requires both renderer compromise and user interaction.

Business impact

While this vulnerability requires a prior renderer compromise, successful exploitation could result in complete system takeover, data exfiltration, lateral movement, or deployment of persistent malware. Organizations with browsers exposed to untrusted content or web-based attacks face elevated risk. The sandbox escape capability amplifies the business impact of any renderer-level exploit, making this a critical threat even though initial access to the renderer is a prerequisite.

Affected systems

Google Chrome prior to version 148.0.7778.216 running on Windows, macOS, and Linux systems is affected. The vulnerability is platform-agnostic within the affected Chrome versions; however, users on these operating systems who use affected Chrome versions should prioritize patching.

Exploitability

Exploitation requires two conditions: (1) the attacker must already have code execution in the Chrome renderer process, and (2) the user must visit or interact with a specially crafted webpage. This is not a direct, unauthenticated remote code execution. The attack surface is limited to users and environments where renderer-level exploits are viable, such as targeted attacks on high-value targets or chained exploits following browser vulnerabilities. The vulnerability is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog as of the last update.

Remediation

Update Google Chrome to version 148.0.7778.216 or later. Verify this version number against the official Chromium release notes and Google's security updates. Users on Windows, macOS, and Linux should check for automatic updates or manually trigger the update through Chrome's Settings menu. Organizations should deploy this patch across managed systems promptly given the sandbox escape nature of the flaw.

Patch guidance

Google Chrome updates automatically for most users, but verify the installation by navigating to chrome://settings/help, which will display the current version and trigger any pending updates. For enterprise deployments, use Chrome's managed update policies or your MDM solution to enforce deployment of version 148.0.7778.216 or later. Test patches in non-production environments first if your organization relies on specific Chrome extensions or web applications that may be affected by the update.

Detection guidance

Monitor Chrome version inventory across your organization to identify instances running versions prior to 148.0.7778.216. Endpoint detection and response (EDR) tools should flag unusual privilege escalation or memory corruption attempts. Network detection is limited due to the requirement for prior renderer compromise; focus on identifying initial renderer exploits through web proxy logs, intrusion detection systems, and browser security telemetry. Chromium-based browsers (Edge, Brave, Opera, etc.) should also be checked if they bundle ANGLE or similar graphics libraries.

Why prioritize this

Although exploitation requires renderer compromise, the sandbox escape capability makes this a critical chaining point in multi-stage attacks. Adversaries who have compromised a renderer can use this flaw to gain system-level access without additional vulnerabilities. This significantly lowers the barrier for attackers already inside the browser process. The High CVSS score, broad platform coverage, and sandbox bypass nature warrant immediate patching.

Risk score, explained

The CVSS 3.1 score of 8.3 reflects a High severity vulnerability. The vector (CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:H) indicates: network attack vector (user must visit a webpage), high complexity (renderer must already be compromised), no privileges required initially, user interaction needed, scope change (sandbox escape), and high impact across confidentiality, integrity, and availability. The score balances the serious nature of sandbox escapes against the prerequisite of renderer-level code execution.

Frequently asked questions