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CVE-2026-9942 Google CVE debrief

An uninitialized use vulnerability in ANGLE, the graphics translation layer used by Google Chrome, allows a remote attacker who has already compromised the renderer process to bypass site isolation protections. The vulnerability stems from CWE-457 (Use of Uninitialized Variable) and affects Chrome versions prior to 148.0.7778.216. Successful exploitation requires the attacker to first achieve renderer compromise, then leverage this flaw to escape site isolation boundaries via a crafted HTML page. The Chromium security team has rated this High severity, while NVD assigns a CVSS 3.1 score of 5.0 (Medium) with vector AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:L, reflecting the high attack complexity and prerequisite renderer compromise. Google addressed this in the stable channel update released May 2026. No known exploitation in ransomware campaigns has been reported, and this CVE is not listed in CISA KEV.

Vendor
Google
Product
Chrome
CVSS
MEDIUM 5
CISA KEV
Not listed in stored evidence
Original CVE published
2026-05-28
Original CVE updated
2026-05-29
Advisory published
2026-05-28
Advisory updated
2026-05-29

Who should care

Organizations with managed Chrome deployments, security teams defending against advanced persistent threats targeting browsers, and users handling sensitive cross-origin data in web applications. The prerequisite renderer compromise indicates this flaw is typically chained with other vulnerabilities rather than exploited in isolation.

Technical summary

The vulnerability exists in ANGLE (Almost Native Graphics Layer Engine), which translates OpenGL ES API calls to platform-native graphics APIs. An uninitialized variable condition permits a compromised renderer process to manipulate graphics state in a manner that violates site isolation boundaries. Site isolation is a Chrome security architecture that restricts each renderer process to documents from a single site, limiting the impact of renderer compromises. By bypassing this boundary, an attacker could potentially access cross-origin data despite the renderer being confined. The fix in Chrome 148.0.7778.216 properly initializes the affected variable, eliminating the bypass vector. The attack requires user interaction (UI:R) and high complexity (AC:H), with network accessibility (AV:N) but no privileges (PR:N).

Defensive priority

medium

Recommended defensive actions

  • Upgrade Google Chrome to version 148.0.7778.216 or later across all platforms (Windows, macOS, Linux).
  • Verify automatic update mechanisms are enabled for Chrome installations in managed environments.
  • Review browser security settings to ensure site isolation features remain active; this vulnerability weakens but does not disable the protection.
  • Monitor for signs of renderer compromise as a prerequisite exploitation condition, including unexpected process crashes or suspicious extension activity.
  • Apply principle of least privilege for web content by disabling unnecessary browser features and restricting untrusted sites.

Evidence notes

CVE description states 'Uninitialized Use in ANGLE in Google Chrome prior to 148.0.7778.216 allowed a remote attacker who had compromised the renderer process to bypass site isolation via a crafted HTML page.' NVD CPE confirms affected product as google:chrome with versionEndExcluding 148.0.7778.216. CVSS vector from NVD metadata: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:L. Weakness enumeration identifies CWE-457. Chrome release notes and Chromium issue tracker provided as vendor references.

Official resources

2026-05-28