CVE-2026-11256 Overview
CVE-2026-11256 is an integer overflow vulnerability in the GPU component of Google Chrome versions prior to 149.0.7827.53. A remote attacker who has already compromised the renderer process can leverage this flaw to potentially perform a sandbox escape using a crafted HTML page. The issue is tracked under [CWE-125] (Out-of-bounds Read) and affects Chrome installations across Windows, macOS, and Linux. Google's Chromium security team rated the underlying issue as Low severity, while the National Vulnerability Database (NVD) assigned a HIGH severity rating based on the broader sandbox escape impact.
Critical Impact
Successful exploitation chains this integer overflow with a prior renderer compromise to break out of the Chrome sandbox, granting attackers code execution at the privilege level of the GPU process.
Affected Products
- Google Chrome prior to 149.0.7827.53
- Microsoft Windows installations running affected Chrome versions
- Apple macOS and Linux installations running affected Chrome versions
Discovery Timeline
- 2026-06-05 - CVE-2026-11256 published to NVD
- 2026-06-05 - Last updated in NVD database
Technical Details for CVE-2026-11256
Vulnerability Analysis
The vulnerability resides in Chrome's GPU process, which handles graphics commands forwarded from the sandboxed renderer process. An integer overflow occurs when the GPU process processes attacker-controlled values supplied through an inter-process communication (IPC) channel. The overflow leads to out-of-bounds memory access, mapped to [CWE-125]. Because the GPU process runs with broader privileges than the renderer, corrupting its memory enables escape from Chrome's site isolation sandbox.
Exploitation requires the attacker to first achieve code execution inside the renderer process, typically by chaining a separate renderer-side bug. The attacker then crafts malicious GPU commands that trigger the integer overflow condition. User interaction is required, such as visiting a malicious HTML page. The attack complexity is high because it depends on a multi-stage exploit chain rather than a single-shot remote vulnerability.
Root Cause
The root cause is missing or insufficient validation of size or offset values during arithmetic operations in Chrome's GPU command processing path. When the calculated value wraps around the integer boundary, subsequent memory operations read or write outside the intended buffer.
Attack Vector
The attack vector is network-based and delivered through a crafted HTML page. The exploit flow requires:
- An attacker hosts a malicious page that exploits an unrelated renderer vulnerability.
- The compromised renderer issues crafted GPU IPC messages containing values that trigger the integer overflow.
- Out-of-bounds memory access in the GPU process is used to corrupt control data and escape the sandbox.
Verified exploitation code is not publicly available. Refer to the Chromium Issue Tracker entry for upstream technical context.
// No verified proof-of-concept code is available.
// The vulnerability is described in prose above.
Detection Methods for CVE-2026-11256
Indicators of Compromise
- Unexpected crashes or restarts of the Chrome GPU process (chrome.exe --type=gpu-process) on endpoint telemetry.
- Outbound connections from Chrome processes to newly registered or low-reputation domains hosting HTML payloads.
- Child processes spawned by the GPU process that deviate from normal Chrome process lineage.
Detection Strategies
- Monitor Chrome version inventory across managed endpoints and flag installations below 149.0.7827.53.
- Hunt for anomalous GPU process behavior, including unusual memory allocations or thread creation patterns.
- Correlate browser process crashes with subsequent privilege escalation or persistence activity on the host.
Monitoring Recommendations
- Ingest Chrome crash reports and Windows Error Reporting (WER) events into your security data lake for trend analysis.
- Enable enterprise reporting through Chrome Browser Cloud Management to centralize browser telemetry.
- Alert on EDR detections of process injection or shellcode execution originating from Chrome GPU processes.
How to Mitigate CVE-2026-11256
Immediate Actions Required
- Update Google Chrome to version 149.0.7827.53 or later on all managed endpoints.
- Restart Chrome after the update to ensure the patched binary is active.
- Verify update deployment status through enterprise management tooling and remediate non-compliant hosts.
Patch Information
Google released the fix in the Chrome Stable channel as documented in the Chrome Releases blog. Apply version 149.0.7827.53 or later. Chromium-based browsers (Microsoft Edge, Brave, Opera, Vivaldi) should be updated to versions that incorporate the upstream Chromium fix.
Workarounds
- Block access to untrusted websites through web filtering or DNS-based controls until patching is complete.
- Enforce Chrome auto-update policies via group policy or mobile device management (MDM) to prevent version drift.
- Limit browser execution to standard user contexts and disable unnecessary GPU acceleration features in high-risk environments.
# Verify installed Chrome version on Windows
reg query "HKLM\Software\Google\Chrome\BLBeacon" /v version
# Verify installed Chrome version on macOS
defaults read /Applications/Google\ Chrome.app/Contents/Info CFBundleShortVersionString
# Verify installed Chrome version on Linux
google-chrome --version
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
