CVE-2023-5476 Overview
CVE-2023-5476 is a Use After Free vulnerability in the Blink History component of Google Chrome prior to version 118.0.5993.70. This memory corruption flaw allows a remote attacker to potentially exploit heap corruption through a specially crafted HTML page. When a user visits a malicious webpage, the vulnerability can be triggered, potentially allowing the attacker to execute arbitrary code within the browser's context or cause the browser to crash.
Critical Impact
This vulnerability enables remote attackers to potentially achieve arbitrary code execution or cause denial of service by exploiting heap corruption when users visit malicious web pages.
Affected Products
- Google Chrome versions prior to 118.0.5993.70
- Debian Linux 11.0
- Debian Linux 12.0
Discovery Timeline
- 2023-10-11 - CVE-2023-5476 published to NVD
- 2025-05-01 - Last updated in NVD database
Technical Details for CVE-2023-5476
Vulnerability Analysis
This Use After Free (CWE-416) vulnerability exists in the Blink History component, which is responsible for managing browser history within the Chromium rendering engine. The flaw occurs when memory that has been freed is subsequently accessed, leading to heap corruption. In the context of a web browser, this type of vulnerability is particularly dangerous as it can be triggered remotely simply by convincing a user to visit a malicious website.
When the vulnerable code path is executed, the browser incorrectly references a memory object that has already been deallocated. An attacker can craft malicious HTML content that manipulates the timing and sequence of memory operations to place controlled data in the freed memory location. This can lead to arbitrary code execution with the privileges of the browser process or cause application instability.
Root Cause
The root cause is a Use After Free condition in the Blink History component where memory management is improperly handled. Specifically, an object is freed while references to it still exist in the code, and those dangling references are later dereferenced. This type of vulnerability typically arises from complex object lifecycle management in C++ code, where references to objects are not properly invalidated or checked before use after the object has been destroyed.
Attack Vector
The attack vector is network-based and requires user interaction. An attacker must craft a malicious HTML page designed to trigger the use-after-free condition in the Blink History component. The attack scenario involves:
- The attacker creates a specially crafted webpage containing HTML/JavaScript that manipulates the browser history functionality
- The victim is enticed to visit the malicious page (via phishing, malvertising, or compromised legitimate sites)
- The malicious content triggers the use-after-free condition in the Blink History component
- Heap corruption occurs, potentially allowing the attacker to execute arbitrary code or crash the browser
The vulnerability can be exploited entirely through the browser's rendering of web content, making drive-by attacks possible. For detailed technical information about the vulnerability, refer to the Chromium Bug Report #1474253.
Detection Methods for CVE-2023-5476
Indicators of Compromise
- Unexpected browser crashes or instability when viewing specific web pages
- Anomalous memory allocation patterns in Chrome browser processes
- Suspicious JavaScript activity related to history API manipulation
- Chrome process crashes with heap corruption signatures in crash reports
Detection Strategies
- Monitor for browser process crashes with memory corruption indicators in system logs
- Deploy endpoint detection solutions capable of identifying heap exploitation attempts
- Implement network-level monitoring for connections to known malicious domains serving exploit content
- Review browser telemetry and crash reports for patterns indicative of exploitation attempts
Monitoring Recommendations
- Enable Chrome's built-in crash reporting to capture and analyze potential exploitation attempts
- Monitor endpoint security solutions for alerts related to browser memory corruption
- Track Chrome version compliance across the organization to identify vulnerable installations
- Review network traffic for suspicious HTML content patterns targeting browser vulnerabilities
How to Mitigate CVE-2023-5476
Immediate Actions Required
- Update Google Chrome to version 118.0.5993.70 or later immediately
- For Debian Linux users, apply the security updates from DSA-5526
- Restrict access to untrusted websites until patches are applied
- Consider implementing browser isolation technologies for high-risk users
Patch Information
Google has addressed this vulnerability in Chrome version 118.0.5993.70 released on October 10, 2023. The fix is available through the standard Chrome auto-update mechanism. For detailed patch information, see the Google Chrome Stable Update.
Additional security advisories have been released by downstream vendors:
Workarounds
- Enable Chrome's Site Isolation feature to limit the impact of renderer exploits
- Use browser extensions that block JavaScript execution on untrusted sites
- Consider using a sandboxed browser environment for accessing untrusted content
- Implement network-level controls to block access to known malicious domains
# Verify Chrome version on Linux
google-chrome --version
# Force Chrome update check (Chrome will restart)
# Navigate to: chrome://settings/help
# For Debian systems, apply security updates
sudo apt update
sudo apt upgrade chromium
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
