CVE-2024-9956: Google Chrome Privilege Escalation Flaw

CVE-2024-9956 Overview

CVE-2024-9956 is a privilege escalation vulnerability in Google Chrome on Android caused by an inappropriate implementation in the WebAuthentication API. This flaw exists in Chrome versions prior to 130.0.6723.58 and allows a local attacker to escalate privileges through a crafted HTML page. The vulnerability specifically affects how Chrome handles WebAuthentication (WebAuthn) operations on Android devices, potentially enabling attackers to bypass security controls designed to protect passkey authentication flows.

Critical Impact

A local attacker can exploit improper WebAuthentication implementation to achieve privilege escalation on affected Android devices running vulnerable Chrome versions, potentially compromising passkey-based authentication mechanisms.

Affected Products

• Google Chrome versions prior to 130.0.6723.58
• Google Chrome on Android operating system
• Devices using Chrome's WebAuthentication/Passkey functionality

Discovery Timeline

• October 15, 2024 - CVE-2024-9956 published to NVD
• November 3, 2025 - Last updated in NVD database

Technical Details for CVE-2024-9956

Vulnerability Analysis

The vulnerability resides in Chrome's implementation of the WebAuthentication API on Android platforms. WebAuthentication (WebAuthn) is a W3C standard that enables strong, passwordless authentication using public key cryptography, commonly known as passkeys. The inappropriate implementation allows local attackers to manipulate the authentication flow through specially crafted HTML content, ultimately achieving privilege escalation.

The attack requires local access and user interaction, meaning the victim must visit or interact with a malicious HTML page. Upon successful exploitation, an attacker can gain elevated privileges that could lead to complete compromise of confidentiality, integrity, and availability on the affected system.

Root Cause

The root cause stems from an inappropriate implementation within Chrome's WebAuthentication subsystem on Android. The specific implementation flaw allows for improper handling of WebAuthn requests, which can be exploited when processing maliciously crafted HTML content. This design or implementation error fails to properly validate or restrict certain operations within the authentication context, enabling unauthorized privilege escalation.

Attack Vector

The attack vector is local, requiring the attacker to either have physical access to the device or the ability to deliver a crafted HTML page to the victim. The exploitation scenario involves:

1. An attacker creates a malicious HTML page that targets the WebAuthentication API vulnerability
2. The victim visits the malicious page on an Android device running a vulnerable Chrome version
3. The crafted page triggers the inappropriate implementation in WebAuthn
4. The attacker successfully escalates privileges on the target system

The vulnerability can be exploited through social engineering tactics to lure victims to attacker-controlled web content, or through other vectors that allow delivery of crafted HTML to the target device.

Detection Methods for CVE-2024-9956

Indicators of Compromise

• Unusual WebAuthentication API calls or requests in browser logs
• Unexpected privilege escalation events on Android devices
• Suspicious HTML pages containing WebAuthn-related JavaScript
• Anomalous Chrome process behavior following visits to untrusted websites

Detection Strategies

• Monitor for Chrome versions below 130.0.6723.58 across Android device fleet
• Implement web filtering to detect and block suspicious HTML content targeting WebAuthn
• Deploy endpoint detection solutions to identify privilege escalation attempts on Android
• Review browser activity logs for unusual WebAuthentication API usage patterns

Monitoring Recommendations

• Enable enhanced logging for Chrome browser activities on managed Android devices
• Implement network-level monitoring for access to known malicious domains
• Deploy SentinelOne agents to detect and respond to privilege escalation attempts in real-time
• Configure alerts for any unauthorized changes to system privileges on Android endpoints

How to Mitigate CVE-2024-9956

Immediate Actions Required

• Update Google Chrome on all Android devices to version 130.0.6723.58 or later immediately
• Audit all managed Android devices to identify systems running vulnerable Chrome versions
• Educate users about the risks of visiting untrusted websites, particularly those requesting authentication
• Implement application control policies to ensure Chrome updates are applied automatically

Patch Information

Google has addressed this vulnerability in Chrome version 130.0.6723.58 and later releases. Organizations should ensure all Android devices running Chrome are updated to this version or newer. The security update was announced through the Google Chrome Releases Blog. Additional technical details are available in the Chromium Issue Tracker.

For additional research context on passkey security implications, refer to the Mastersplinter Research on Passkeys.

Workarounds

• Restrict access to untrusted websites on managed Android devices until patching is complete
• Temporarily disable or limit WebAuthn/passkey functionality in enterprise environments where feasible
• Implement network-level controls to block access to potentially malicious content
• Consider using alternative browsers on Android devices while Chrome remains unpatched

# Verify Chrome version on Android devices (via ADB)
adb shell pm dump com.android.chrome | grep versionName
# Expected output should show version 130.0.6723.58 or higher

# For enterprise deployments, ensure Chrome policies enforce automatic updates
# Configure managed Chrome browser policies through Google Admin Console