CVE-2024-0024: Google Android Privilege Escalation Flaw

CVE-2024-0024 Overview

CVE-2024-0024 is a privilege escalation vulnerability affecting multiple methods within Android's UserManagerService.java. The vulnerability stems from improper input validation that can lead to a failure to persist or enforce user restrictions. An attacker could exploit this flaw to achieve local privilege escalation without requiring additional execution privileges, though user interaction is necessary for successful exploitation.

Critical Impact

Local privilege escalation in Android devices through improper input validation in UserManagerService, potentially allowing attackers to bypass user restrictions and gain elevated system privileges.

Affected Products

• Google Android 12.0
• Google Android 12.1
• Google Android 13.0
• Google Android 14.0

Discovery Timeline

• May 7, 2024 - CVE-2024-0024 published to NVD
• December 17, 2024 - Last updated in NVD database

Technical Details for CVE-2024-0024

Vulnerability Analysis

This vulnerability exists in UserManagerService.java, a core Android framework component responsible for managing user accounts and enforcing user-level restrictions on multi-user Android devices. The flaw allows user restrictions to fail to persist or be properly enforced, which can be leveraged by a malicious application or process to escalate privileges locally.

The vulnerability is classified under CWE-269 (Improper Privilege Management), indicating that the system does not properly manage the assignment, modification, tracking, or checking of privileges for users. The attack requires local access and user interaction, meaning an attacker would typically need to convince a user to install a malicious application or interact with malicious content that triggers the vulnerability.

Root Cause

The root cause of CVE-2024-0024 lies in improper input validation within multiple methods of UserManagerService.java. The service fails to properly validate inputs when handling user restriction operations, leading to a state where user restrictions may not be correctly persisted to storage or enforced at runtime. This validation gap creates an opportunity for privilege escalation without requiring additional execution privileges.

Attack Vector

The attack vector for CVE-2024-0024 is local, requiring the attacker to have some level of access to the target Android device. The exploitation scenario typically involves:

1. A malicious application installed on the device that targets the vulnerable UserManagerService methods
2. User interaction to trigger the vulnerability (e.g., through normal app usage or social engineering)
3. The malicious app exploits the improper input validation to bypass or disable user restrictions
4. The attacker gains elevated privileges on the device, potentially accessing restricted data or functionality

The vulnerability mechanism involves crafting specific inputs to the affected UserManagerService methods that cause the service to fail in persisting or enforcing user restrictions. Technical details can be found in the Android Source Code Change which contains the patch commit.

Detection Methods for CVE-2024-0024

Indicators of Compromise

• Unexpected changes to user restriction settings on Android devices
• Applications requesting or obtaining permissions beyond their declared scope
• Anomalous behavior from installed applications attempting to access restricted system functions
• Log entries in UserManagerService showing unusual user restriction modifications

Detection Strategies

• Monitor system logs for suspicious activity related to UserManagerService and user restriction changes
• Implement application behavioral analysis to detect privilege escalation attempts
• Use mobile threat defense solutions to identify malicious applications targeting system services
• Review installed applications for those requesting excessive permissions or exhibiting suspicious behavior

Monitoring Recommendations

• Enable verbose logging for UserManagerService operations on managed devices
• Deploy endpoint detection and response (EDR) solutions capable of monitoring Android system service interactions
• Implement application allow-listing policies on enterprise-managed devices
• Regularly audit user restrictions and permission grants on Android devices in your environment

How to Mitigate CVE-2024-0024

Immediate Actions Required

• Update all affected Android devices to the May 2024 security patch level or later
• Review and audit installed applications on Android devices for potential malicious behavior
• Implement mobile device management (MDM) policies to enforce security updates
• Restrict installation of applications from unknown sources

Patch Information

Google has addressed this vulnerability in the May 2024 Android Security Bulletin. The fix is available through the patch at commit 6a9250ec7fc9801a883cedd7860076f42fb518ac in the Android frameworks/base repository. Organizations should ensure all affected devices are updated to the May 2024 security patch level. For detailed patch information, refer to the Android Security Bulletin May 2024.

Workarounds

• Restrict application installation to trusted sources (Google Play Store or enterprise app stores)
• Implement strict application vetting processes before deployment on enterprise devices
• Use mobile threat defense solutions to detect and block exploitation attempts
• Consider network segmentation to limit the impact of potentially compromised devices

# Verify Android security patch level via ADB
adb shell getprop ro.build.version.security_patch
# Expected output should be 2024-05-01 or later

# Check for UserManagerService-related logs
adb logcat -d | grep -i "UserManagerService"