CVE-2023-0941: Google Chrome Use After Free Vulnerability

CVE-2023-0941 Overview

CVE-2023-0941 is a use after free vulnerability discovered in the Prompts component of Google Chrome prior to version 110.0.5481.177. This memory corruption flaw allows a remote attacker to potentially exploit heap corruption through a specially crafted HTML page. The Chromium security team has classified this vulnerability as Critical severity.

Use after free vulnerabilities occur when a program continues to use a pointer after the memory it references has been freed. In the context of browser security, this class of vulnerability is particularly dangerous as it can lead to arbitrary code execution within the browser's process, potentially allowing attackers to escape the browser sandbox or compromise user data.

Critical Impact

Remote attackers can potentially achieve heap corruption and code execution by convincing users to visit a malicious webpage containing crafted HTML content.

Affected Products

• Google Chrome versions prior to 110.0.5481.177
• Chromium-based browsers using affected Chrome components
• All desktop platforms running vulnerable Chrome versions

Discovery Timeline

• February 22, 2023 - CVE-2023-0941 published to NVD
• November 21, 2024 - Last updated in NVD database

Technical Details for CVE-2023-0941

Vulnerability Analysis

This vulnerability resides in Chrome's Prompts component, which handles various browser dialog and prompt interactions with users. The use after free condition (CWE-416) occurs when the browser incorrectly manages memory during prompt-related operations, leading to a scenario where freed memory is subsequently accessed.

When exploited, this vulnerability can result in heap corruption, which attackers may leverage to achieve arbitrary code execution within the context of the Chrome renderer process. The attack requires user interaction—specifically, the victim must navigate to a malicious webpage—but requires no special privileges or authentication.

Root Cause

The root cause of CVE-2023-0941 is improper memory management in Chrome's Prompts component. The vulnerability stems from a use after free condition where an object in memory is freed but a reference (dangling pointer) to that memory location is retained and later dereferenced. When the browser attempts to access this freed memory, it may read or write to memory that has been reallocated for other purposes, leading to heap corruption.

This type of memory safety issue is common in C++ codebases like Chromium, where manual memory management can lead to complex object lifetime issues, particularly in asynchronous callback scenarios that are prevalent in browser prompt handling.

Attack Vector

The attack vector for this vulnerability is network-based, requiring user interaction. An attacker would need to:

1. Create a malicious webpage containing specially crafted HTML content designed to trigger the use after free condition in the Prompts component
2. Convince a victim to visit the malicious page through social engineering techniques such as phishing emails, malicious advertisements, or compromised legitimate websites
3. Once the victim's vulnerable Chrome browser processes the crafted content, the heap corruption occurs

The crafted HTML page must manipulate the browser's prompt handling in a specific sequence to trigger the memory corruption condition. Successful exploitation could allow the attacker to execute arbitrary code within the browser process, potentially leading to further system compromise.

For detailed technical information about this vulnerability, refer to the Chromium Bug Report #1415366 and the Google Chrome Update Announcement.

Detection Methods for CVE-2023-0941

Indicators of Compromise

• Unexpected browser crashes or instability when viewing web content
• Chrome crash reports indicating memory corruption in Prompts-related components
• Suspicious outbound network connections following webpage visits
• Anomalous process behavior spawned from Chrome browser processes

Detection Strategies

• Monitor Chrome version across the enterprise to identify instances running versions prior to 110.0.5481.177
• Implement endpoint detection rules to identify unusual memory allocation patterns or heap spray attempts in browser processes
• Deploy network security monitoring to detect connections to known malicious domains that may host exploit pages
• Review browser crash telemetry for patterns indicating exploitation attempts

Monitoring Recommendations

• Enable Chrome's built-in crash reporting and review crash dumps for signs of memory corruption
• Configure SIEM rules to alert on multiple Chrome crashes from the same endpoint in short time periods
• Monitor for process injection or unexpected child process creation from Chrome
• Implement browser isolation solutions to contain potential exploitation attempts

How to Mitigate CVE-2023-0941

Immediate Actions Required

• Update Google Chrome to version 110.0.5481.177 or later immediately
• Enable automatic updates for Chrome across all managed endpoints
• Verify Chrome version compliance using endpoint management tools
• Consider implementing browser isolation for high-risk users until patching is complete

Patch Information

Google has released a security update addressing this vulnerability in Chrome version 110.0.5481.177. The fix was announced on February 22, 2023, through the Google Chrome Update Announcement.

Organizations using Chromium-based browsers or embedded Chromium components should verify that their vendors have incorporated the patched Chromium version. Linux distributions such as Gentoo have released their own advisories—see the Gentoo GLSA 202309-17 Advisory for distribution-specific guidance.

To verify your Chrome version, navigate to chrome://settings/help or click the three-dot menu → Help → About Google Chrome. The browser will automatically check for and install available updates.

Workarounds

• Implement browser isolation or sandboxing solutions to limit the impact of potential exploitation
• Use web filtering to block access to untrusted or malicious websites
• Deploy network-level protection to identify and block known exploit delivery domains
• Consider temporarily using an alternative browser if immediate patching is not possible

# Verify Chrome version on Linux systems
google-chrome --version
# Expected output should show version 110.0.5481.177 or higher

# Force Chrome update check on Windows (PowerShell)
# Navigate to chrome://settings/help in browser
# Or use enterprise deployment tools like SCCM/Intune for managed updates