CVE-2026-11154: Chrome Dawn Use-After-Free Sandbox Escape Vulnerability

Technical summary

CVE-2026-11154 is a use-after-free vulnerability (CWE-416) in the Dawn graphics subsystem of Google Chrome. The flaw enables a remote attacker operating within a compromised renderer process to craft a malicious HTML page that triggers memory safety violations. When processed, this can escape the browser's sandbox isolation, potentially allowing arbitrary code execution with the privileges of the user running Chrome. The Chromium project rated this Medium severity internally, but the assigned CVSS 3.1 score of 7.5 (HIGH) reflects the sandbox escape impact and requirement for user interaction combined with prior renderer compromise.

Business impact

Successful exploitation could result in complete system compromise following a two-stage attack: first gaining renderer process access (via existing RCE or other means), then leveraging this vulnerability to bypass sandboxing and execute code outside the browser context. For organizations where users browse untrusted content or receive targeted phishing with weaponized HTML, this represents a path to lateral movement, credential theft, and data exfiltration at the OS level. Delayed patching increases the window of exposure if this vulnerability is discovered in active exploits.

Affected systems

Google Chrome versions prior to 149.0.7827.53 are directly affected. The vulnerability's runtime behavior depends on the underlying operating system (Windows, macOS, or Linux), though the flaw itself is platform-agnostic at the Chrome/Dawn level. Any user running unpatched Chrome on supported operating systems is at risk if they encounter malicious content.

Exploitability

Exploitation requires two prerequisites: (1) prior compromise of the renderer process, and (2) user interaction to open a crafted HTML page. The renderer compromise barrier is significant—it typically requires a separate vulnerability or social engineering—but once achieved, the sandbox escape is triggered by HTML content, which is relatively easy to deliver. The use-after-free pattern is well-studied in browser security, though specific exploitation details depend on memory layout and mitigation bypass techniques. Without KEV inclusion or public proof-of-concept reports, opportunistic mass exploitation is less likely, but targeted campaigns against high-value targets could feasibly weaponize this.

Remediation

Update Google Chrome to version 149.0.7827.53 or later. Chrome auto-updates by default on most platforms, but users should verify they are on the latest stable release. Organizations can enforce updates via Chrome management policies (Admin Console, GPO, or device enrollment). Verify patch deployment across endpoints and monitor for any lingering unpatched instances in user-managed devices or legacy systems.

Patch guidance

Verify that your Chrome installation has updated to 149.0.7827.53 or later by checking Settings > About Google Chrome. The browser will automatically check for and install updates, restarting on next launch. For managed deployments, review your Chrome enterprise policies to ensure auto-updates are enabled and test on a small cohort before broad rollout. Organizations using Chromebook deployments should note that updates are handled by your cloud enrollment domain; verify your device management console reports current Chrome versions.

Detection guidance

Monitor for use-after-free crash reports or core dumps mentioning the Dawn graphics subsystem, particularly those triggered by HTML content. Endpoint detection and response (EDR) tools can alert on Chrome process memory access violations or sandbox boundary crossings. Network-level detection is limited, as the malicious content is HTML; consider monitoring inbound phishing and social engineering campaigns that might deliver such payloads. Internal logs of Chrome version compliance help identify remaining unpatched instances.

Why prioritize this

Although this vulnerability requires prior renderer compromise, the sandbox escape capability elevates risk significantly. A successful exploit could grant an attacker OS-level access, enabling persistence, lateral movement, and data theft beyond what a confined renderer process permits. The HIGH CVSS score (7.5) reflects the severity of sandbox bypass; however, lack of KEV inclusion and absence of public exploits mean this is not yet an imminent mass-exploitation threat. Prioritize patching for users in high-risk roles (finance, government, legal) and organizations facing advanced threats, while scheduling standard deployments for broader user bases.

Risk score, explained

The CVSS 3.1 score of 7.5 (HIGH) is derived from network attack vector, high confidentiality/integrity/availability impact, and user interaction requirement, offset slightly by the requirement that the renderer process be pre-compromised (reflected in the AC:H complexity modifier). This score appropriately weighs the severe consequence (sandbox escape) against the multiple conditions needed to reach exploitability. The gap between Chromium's internal Medium rating and the CVSS HIGH score reflects the context-dependent nature of risk: within a browser component lifecycle, Medium is reasonable; from a system security perspective, sandbox escape is HIGH impact.

Frequently asked questions