CVE-2026-13803: Chrome Type Confusion Sandbox Escape (v150.0.7871.47)

Technical summary

CVE-2026-13803 is a type confusion vulnerability (CWE-843) in the Chrome Tabs component prior to version 150.0.7871.47. The flaw exists in how Chrome handles type validation when processing certain HTML constructs related to tab objects. An attacker controlling the renderer process can craft malicious HTML that triggers incorrect type interpretation, bypassing Chrome's inter-process communication (IPC) security boundaries and sandbox isolation. The attack results in arbitrary code execution at the system level with the privileges of the browser process. The Chromium project classified this as High severity.

Business impact

This vulnerability represents a critical escalation pathway for attackers who have already achieved initial renderer process compromise (via malicious websites, vulnerable extensions, or memory corruption flaws). While it requires a prior compromise, successful exploitation grants attackers complete system access, enabling data exfiltration, malware installation, lateral movement, and persistent system compromise. Organizations should treat this as a priority remediation target given the severity of sandbox escape attacks in real-world threat scenarios.

Affected systems

Google Chrome versions prior to 150.0.7871.47 are vulnerable. This includes all earlier stable, beta, and development releases up to that version. Users of Chromium-based browsers (Edge, Brave, Opera, etc.) built from vulnerable Chromium source code are also at risk, though patch availability varies by vendor. Check your browser's About page (chrome://about or equivalent) to confirm version and update status.

Exploitability

Exploitation requires two preconditions: (1) the attacker must first compromise the Chrome renderer process, typically via a separate vulnerability or malicious website, and (2) the user must visit or be redirected to a crafted HTML page. While the attack chain is complex, both components are plausible in targeted scenarios. The CVSS vector (AC:H) reflects the high complexity of achieving renderer compromise, but once achieved, the type confusion itself is reliably exploitable. This is not a zero-click vulnerability and does not currently appear on CISA's Known Exploited Vulnerabilities (KEV) catalog.

Remediation

Immediately update Google Chrome to version 150.0.7871.47 or later. Chrome typically auto-updates, but users can manually trigger updates via Settings > About Chrome. Organizations should verify patch deployment across all managed Chrome instances and confirm version compliance. For Chromium-based browsers, check vendor advisories for equivalent patched versions. No workarounds mitigate the sandbox escape itself; patching is the only mitigation.

Patch guidance

Google Chrome 150.0.7871.47 and later contain the fix. Users should verify their installed version through chrome://version or Settings > About Chrome, which will auto-download and stage the patch. The update typically requires a browser restart to apply. Organizations using Chrome Enterprise should push updates via Group Policy (Windows), Mobile Device Management (MDM), or equivalent deployment tools. Test patching in a limited environment first to confirm compatibility with any critical extensions or legacy web applications. Verify all renderer processes have terminated and been replaced with the patched version.

Detection guidance

Monitor for Chrome version compliance: versions prior to 150.0.7871.47 are vulnerable. Use endpoint detection and response (EDR) tools to flag outdated Chrome installations. Look for suspicious IPC messages or memory access patterns targeting Chrome's tab objects if you have browser-level telemetry. Organizations may also track Chrome crash dumps for type confusion-related crashes (often accompanied by unusual stack traces in tab handling code). However, detection of active exploitation is difficult without deep runtime instrumentation; prevention via patching is far more effective.

Why prioritize this

Although this CVE requires prior renderer compromise, sandbox escapes are among the most dangerous browser vulnerabilities because they enable attackers to move from a sandboxed process to full system access. The CVSS score of 8.3 (HIGH) reflects the severity of the impact. The attack chain, while multi-step, is realistic in targeted campaigns. Patch deployment should be prioritized within your normal update cycle, especially for systems exposed to untrusted web content or high-value targets.

Risk score, explained

The CVSS 3.1 score of 8.3 is driven by: (1) High impact across confidentiality, integrity, and availability; (2) Network attack vector (the crafted HTML can be delivered remotely); (3) No authentication required; (4) User interaction required (visiting the malicious page); (5) Changed scope (sandbox escape extends impact beyond the renderer process). The High complexity (AC:H) reflects the prerequisite renderer compromise, preventing a Critical rating, but the impact remains severe.

Frequently asked questions