CVE-2026-6296: Google Chrome ANGLE Buffer Overflow Flaw

CVE-2026-6296 Overview

A critical heap buffer overflow vulnerability exists in ANGLE (Almost Native Graphics Layer Engine) in Google Chrome prior to version 147.0.7727.101. This memory corruption flaw allows a remote attacker to potentially perform a sandbox escape by enticing a user to visit a maliciously crafted HTML page. ANGLE is Chrome's graphics abstraction layer responsible for translating OpenGL ES calls to the underlying graphics APIs, making this a particularly dangerous attack surface.

Critical Impact

This vulnerability enables sandbox escape, allowing attackers to break out of Chrome's security sandbox and potentially execute arbitrary code with elevated privileges on the underlying system.

Affected Products

• Google Chrome prior to version 147.0.7727.101
• Chromium-based browsers using vulnerable ANGLE implementations
• Desktop platforms running affected Chrome versions (Windows, macOS, Linux)

Discovery Timeline

• 2026-04-15 - CVE CVE-2026-6296 published to NVD
• 2026-04-15 - Last updated in NVD database

Technical Details for CVE-2026-6296

Vulnerability Analysis

This vulnerability is classified as CWE-122 (Heap-based Buffer Overflow), a memory corruption issue occurring when data is written beyond the allocated boundaries of a heap buffer. In the context of ANGLE, the graphics abstraction layer processes WebGL and other graphics-related content from web pages, making it an attractive target for browser-based attacks.

The heap buffer overflow occurs during the processing of specially crafted graphics operations. When exploited, the attacker can corrupt adjacent heap memory, potentially overwriting critical data structures or function pointers. The changed scope indicator in the vulnerability assessment suggests that successful exploitation allows the attacker to affect resources beyond the vulnerable component's security scope—specifically enabling sandbox escape.

The network-based attack vector requires user interaction (visiting a malicious page), but no authentication or special privileges are needed to trigger the vulnerability. Once triggered, the potential for sandbox escape represents a severe security boundary violation, as Chrome's sandbox is a fundamental security control designed to isolate web content from the operating system.

Root Cause

The root cause is a heap-based buffer overflow (CWE-122) in the ANGLE graphics abstraction layer. This occurs when the component fails to properly validate buffer boundaries during graphics operations, allowing attacker-controlled data to overflow allocated heap memory regions.

Attack Vector

The attack is delivered remotely over the network via a crafted HTML page containing malicious graphics content. When a user navigates to or is redirected to the attacker-controlled page, the malicious WebGL or graphics operations trigger the heap buffer overflow in ANGLE. The exploitation flow involves:

1. Attacker hosts a malicious web page with crafted graphics content
2. Victim navigates to the malicious page (user interaction required)
3. Chrome's ANGLE component processes the malicious graphics operations
4. Heap buffer overflow occurs, corrupting memory
5. Attacker achieves sandbox escape and potential code execution

The vulnerability can be triggered through WebGL content, Canvas operations, or other graphics-intensive web features that utilize ANGLE for hardware-accelerated rendering.

Detection Methods for CVE-2026-6296

Indicators of Compromise

• Abnormal Chrome renderer process crashes or unexpected termination patterns
• Memory access violations or heap corruption errors in Chrome crash reports referencing ANGLE or graphics components
• Suspicious network connections originating from Chrome processes after visiting untrusted websites

Detection Strategies

• Monitor for Chrome renderer process crashes with heap corruption signatures in ANGLE-related modules
• Implement browser isolation solutions to contain potential exploitation attempts
• Deploy endpoint detection and response (EDR) solutions capable of detecting sandbox escape behavior
• Monitor for unusual child process spawning from Chrome renderer processes

Monitoring Recommendations

• Enable Chrome crash reporting and analyze crash dumps for ANGLE-related heap overflow indicators
• Monitor system logs for signs of privilege escalation following browser activity
• Implement network monitoring to detect suspicious post-exploitation communication patterns

How to Mitigate CVE-2026-6296

Immediate Actions Required

• Update Google Chrome to version 147.0.7727.101 or later immediately
• Enable automatic updates for Chrome to ensure timely delivery of security patches
• Consider temporarily disabling WebGL in Chrome settings if immediate patching is not possible
• Implement browser isolation for high-risk browsing activities

Patch Information

Google has released Chrome version 147.0.7727.101 to address this vulnerability. The patch resolves the heap buffer overflow in ANGLE by implementing proper boundary checking during graphics operations. Organizations should prioritize deployment of this update across all endpoints.

For detailed information about the fix, refer to the Google Chrome Stable Update announcement and Chromium Issue #490170083.

Workarounds

• Disable WebGL by navigating to chrome://flags and setting WebGL to disabled (may impact web application functionality)
• Use browser isolation solutions to contain renderer process compromises
• Implement strict Content Security Policy headers on managed web properties to limit graphics API abuse
• Consider using alternative browsers temporarily until Chrome can be updated

# Configuration example
# Disable WebGL via Chrome command-line flags
# Launch Chrome with hardware acceleration disabled as a temporary mitigation
google-chrome --disable-webgl --disable-gpu

# For enterprise deployment, configure Chrome policies
# Create policy file: /etc/opt/chrome/policies/managed/disable_webgl.json
{
  "WebGLAllowed": false
}