CVE-2024-7966: Google Chrome Buffer Overflow Vulnerability

CVE-2024-7966 Overview

CVE-2024-7966 is an out-of-bounds memory access vulnerability in the Skia graphics library component of Google Chrome. The flaw affects Chrome versions prior to 128.0.6613.84 and allows a remote attacker who has already compromised the renderer process to perform out-of-bounds memory access via a crafted HTML page. This vulnerability was classified with High severity by the Chromium security team.

Critical Impact

Successful exploitation enables attackers who have compromised Chrome's renderer process to access memory outside allocated boundaries, potentially leading to information disclosure, arbitrary code execution, or browser crashes.

Affected Products

• Google Chrome versions prior to 128.0.6613.84
• Chromium-based browsers using vulnerable Skia library versions
• All platforms running affected Chrome versions (Windows, macOS, Linux)

Discovery Timeline

• 2024-08-21 - CVE-2024-7966 published to NVD
• 2024-08-27 - Last updated in NVD database

Technical Details for CVE-2024-7966

Vulnerability Analysis

This vulnerability resides in Skia, an open-source 2D graphics library that serves as the graphics engine for Google Chrome and other Chromium-based browsers. Skia handles critical rendering operations including text rendering, image processing, and vector graphics. The out-of-bounds memory access vulnerability (CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer, CWE-125: Out-of-bounds Read) occurs when the Skia library processes specially crafted graphical content.

The exploitation scenario requires an attacker to first compromise the Chrome renderer process through another vulnerability or technique, after which they can leverage this Skia vulnerability to access memory regions outside the intended boundaries. This attack chain approach indicates the vulnerability is part of a multi-stage exploit scenario.

Root Cause

The root cause stems from improper boundary checking within Skia's memory operations when processing certain graphical elements. When handling maliciously crafted HTML content that triggers specific rendering paths, the Skia library fails to properly validate memory access boundaries, allowing read or write operations to occur outside allocated buffer regions.

Attack Vector

The attack requires user interaction - a victim must navigate to or be redirected to an attacker-controlled webpage containing the malicious HTML content. The attack is network-based and does not require authentication, but does require prior compromise of the renderer process, suggesting this vulnerability would typically be chained with another exploit.

The vulnerability can be triggered through:

• Maliciously crafted HTML pages with specially designed graphical elements
• Embedded images or SVG content designed to trigger vulnerable code paths
• JavaScript-driven dynamic content that manipulates the rendering pipeline

Detection Methods for CVE-2024-7966

Indicators of Compromise

• Unexpected Chrome renderer process crashes with memory-related error signatures
• Unusual memory access patterns in browser process monitoring
• Suspicious network requests to unknown domains delivering HTML/graphical content
• Anomalous browser behavior following visits to untrusted websites

Detection Strategies

• Monitor for Chrome crash reports indicating Skia-related memory violations
• Implement network traffic analysis to detect delivery of exploit pages
• Deploy endpoint detection solutions capable of identifying renderer process anomalies
• Review browser version inventory to identify unpatched Chrome installations

Monitoring Recommendations

• Enable Chrome crash reporting and monitor for patterns indicating exploitation attempts
• Implement browser version monitoring across the organization to track patching status
• Configure SIEM rules to correlate browser crashes with suspicious network activity
• Monitor for unusual child process spawning from Chrome renderer processes

How to Mitigate CVE-2024-7966

Immediate Actions Required

• Update Google Chrome to version 128.0.6613.84 or later immediately
• Enable automatic Chrome updates across all managed endpoints
• Implement browser isolation for high-risk users or sensitive environments
• Review and restrict access to untrusted websites through web filtering

Patch Information

Google has addressed this vulnerability in Chrome version 128.0.6613.84. The fix was announced in the Google Chrome Stable Channel Update on August 21, 2024. Organizations should ensure all Chrome installations are updated to this version or later. Additional technical details can be found in the Chromium Issue Tracker.

Workarounds

• Implement network-level blocking of known malicious domains delivering exploit content
• Consider using browser isolation technologies to contain potential renderer compromises
• Enable Chrome's Site Isolation feature to provide additional process-level protection
• Restrict browser usage to trusted sites only until patching is complete

# Verify Chrome version on Windows (PowerShell)
(Get-Item "C:\Program Files\Google\Chrome\Application\chrome.exe").VersionInfo.FileVersion

# Verify Chrome version on macOS
/Applications/Google\ Chrome.app/Contents/MacOS/Google\ Chrome --version

# Verify Chrome version on Linux
google-chrome --version