CVE-2026-118333: CVE-2026-118333: Missing authorization in Video in Google Chrome prior to 156.0.8078.73 allowed a remote at…

CVE-2026-118333 at a glance

CVE-2026-118333 is a critical-severity Missing Authorization vulnerability in Google Chrome, with a CVSS 3.1 base score of 9.3. NVD published it on 2026-10-28 and classifies the weakness as CWE-862. FIRST EPSS puts the probability of exploitation activity in the next 30 days at 0.20% (percentile 10.0, scored 2026-11-03). NVD configuration data lists a fixed release for 1 product, for example google chrome 156.0.8078.73. CVERadar maps 1 MITRE ATT&CK technique across Privilege Escalation, inferred from the CWE and the description. Its CVERadar threat level is 47/100.

What it is

Missing authorization in Video in Google Chrome prior to 156.0.8078.73 allowed a remote attacker to bypass web origin policy via a crafted HTML page. (Chromium security severity: High)

Patches, mitigations and detection

Fixed versions

• google chrome: upgrade to 156.0.8078.73 or later

Derived from the NVD CPE configuration (versionEndExcluding / versionEndIncluding). Always confirm with the vendor advisory.

Vendor advisories and patches

• Google vendor advisory (chromereleases.googleblog.com) (Release Notes, Vendor Advisory)

MITRE ATT&CK mitigations for this chain

• M1051 Update Software (for T1068) : Update software regularly by employing patch management for internal enterprise endpoints and servers.
• M1050 Exploit Protection (for T1068) : Security applications that look for behavior used during exploitation such as Windows Defender Exploit Guard (WDEG) and the Enhanced Mitigation Experience Toolkit (EMET) can be used to mitigate some exploitation behavior. Control flow integrity checking is another way to potentially identify and stop a software exploi
• M1048 Application Isolation and Sandboxing (for T1068) : Make it difficult for adversaries to advance their operation through exploitation of undiscovered or unpatched vulnerabilities by using sandboxing. Other types of virtualization and application microsegmentation may also mitigate the impact of some types of exploitation. Risks of additional exploits and weaknesses in t
• M1019 Threat Intelligence Program (for T1068) : Develop a robust cyber threat intelligence capability to determine what types and levels of threat may use software exploits and 0-days against a particular organization.
• M1038 Execution Prevention (for T1068) : Consider blocking the execution of known vulnerable drivers that adversaries may exploit to execute code in kernel mode. Validate driver block rules in audit mode to ensure stability prior to production deployment.

Detection Generic guidance

• Privilege Escalation: Alert on processes gaining SYSTEM/root unexpectedly, and on exploitation crashes of privileged services.

Response checklist Generic guidance

1. Inventory: find every instance of the affected product and version (include internet-facing and forgotten ones).
2. Patch or mitigate per the vendor advisory; if you cannot patch, remove internet exposure or apply the vendor workaround.
3. Assume compromise if the system was exposed before patching: hunt for the indicators in the advisory and review logs back to the disclosure date.
4. Rotate credentials and secrets stored on or used by the affected system if compromise cannot be ruled out.

If an exploit for Google Chrome lands on a workstation, detection is what catches it; see LayerLogix endpoint protection.