CVE-2025-0077: Google Android Privilege Escalation Flaw

CVE-2025-0077 Overview

CVE-2025-0077 is a race condition vulnerability discovered in multiple functions of UserController.java within the Android framework. This security flaw enables a lock screen bypass that can lead to local escalation of privilege without requiring any additional execution privileges or user interaction.

Critical Impact

Local attackers can bypass the device lock screen through a race condition, potentially gaining unauthorized access to user data and device functionality without user interaction.

Affected Products

• Google Android 15.0

Discovery Timeline

• 2025-09-04 - CVE-2025-0077 published to NVD
• 2025-09-05 - Last updated in NVD database

Technical Details for CVE-2025-0077

Vulnerability Analysis

This vulnerability resides in the UserController.java component of the Android framework base. The flaw manifests as a race condition within multiple functions responsible for managing user session states and lock screen enforcement. When exploited, the race condition allows an attacker to bypass the lock screen mechanism, effectively circumventing the device's primary physical security barrier.

The vulnerability is particularly concerning because it requires no user interaction and no additional execution privileges to exploit. An attacker with local access to the device can trigger the race condition to gain unauthorized access. The impact includes exposure of confidential information stored on the device, though the vulnerability does not directly enable system modification or denial of service.

Root Cause

The root cause is a Time-of-Check Time-of-Use (TOCTOU) race condition in the UserController.java file. The vulnerability arises from improper synchronization when checking and enforcing the lock screen state. During the brief window between the security check and the enforcement action, an attacker can manipulate the system state to bypass the lock screen validation entirely.

This type of vulnerability typically occurs when multiple threads or processes access shared resources without proper locking mechanisms, allowing one operation to interfere with another in unexpected ways.

Attack Vector

The attack vector is local, meaning an attacker needs physical access to the Android device to exploit this vulnerability. The exploitation scenario involves triggering specific operations that interact with the UserController during vulnerable timing windows, allowing the attacker to slip past the lock screen authentication.

Since no user interaction is required and no elevated privileges are needed to trigger the race condition, an attacker who gains temporary physical access to an unattended device could potentially exploit this vulnerability to access protected user data.

Detection Methods for CVE-2025-0077

Indicators of Compromise

• Unusual system log entries related to UserController showing abnormal user session state transitions
• Evidence of lock screen bypass events in device security audit logs
• Unexpected user session activations without corresponding authentication events

Detection Strategies

• Monitor Android system logs for race condition indicators in user management components
• Implement Mobile Device Management (MDM) solutions that can detect unauthorized access patterns
• Review device audit logs for lock screen bypass attempts or anomalous authentication sequences

Monitoring Recommendations

• Enable verbose logging for Android framework security components during security assessments
• Deploy endpoint detection solutions capable of monitoring Android framework behavior
• Establish baseline device access patterns to identify deviations that may indicate exploitation attempts

How to Mitigate CVE-2025-0077

Immediate Actions Required

• Update affected Android 15.0 devices to the latest security patch level addressing this vulnerability
• Review the Android Security Bulletin May 2025 for complete patch information
• Implement physical security controls to limit unauthorized device access until patches are applied
• Consider additional authentication mechanisms as a defense-in-depth measure

Patch Information

Google has released multiple patches to address this vulnerability in the Android framework base. The fixes are documented in the Android Security Bulletin May 2025. The following commits address CVE-2025-0077:

• Commit 37a4df78c7e1b91066b341b05fb767f27c5da835
• Commit 3b04c948727c35e6ad429eefc6aaa9c261addf12
• Commit 5f59ac63cb7042d58dae196e890ec52424ebe8b5
• Commit 8c290a4d87c27a4ad65757e97ff9e634d9fe865e
• Commit a09b6451c99f8aa99c49a0e584e12be455c414f4
• Commit c059123b8e9c0920a30f896513116a8b88bfc4e1

Organizations should apply the May 2025 security patch level or later to remediate this vulnerability.

Workarounds

• Maintain strict physical security controls for devices that cannot be immediately patched
• Enable additional device encryption to protect data at rest even if lock screen is bypassed
• Implement MDM policies to enforce device lockdown and remote wipe capabilities
• Consider disabling affected devices in high-security environments until patches are applied