CVE-2026-0005 Overview
CVE-2026-0005 is an authorization bypass vulnerability in the Android Keyguard service that allows partial bypass of app pinning functionality. The vulnerability exists in the onServiceDisconnected method of KeyguardServiceDelegate.java, where a missing permission check enables limited interaction with other apps without requiring the Lock Screen Knowledge Factor (LSKF). This could lead to local information disclosure, with the extent of interaction and impact being app-dependent. No additional execution privileges are required, and user interaction is not needed for exploitation.
Critical Impact
Local information disclosure through app pinning bypass allowing unauthorized interaction with pinned apps on Android devices running versions 14.0, 15.0, and 16.0.
Affected Products
- Google Android 14.0
- Google Android 15.0
- Google Android 16.0
Discovery Timeline
- 2026-03-02 - CVE CVE-2026-0005 published to NVD
- 2026-03-03 - Last updated in NVD database
Technical Details for CVE-2026-0005
Vulnerability Analysis
The vulnerability resides in KeyguardServiceDelegate.java, specifically within the onServiceDisconnected method. This method is invoked when the Keyguard service connection is unexpectedly terminated. Due to a missing permission check in this code path, the security mechanism that enforces app pinning can be partially bypassed.
App pinning (also known as screen pinning) is an Android security feature that restricts the device to displaying only a single app until the user authenticates using their Lock Screen Knowledge Factor (LSKF), such as a PIN, pattern, or password. The vulnerability allows limited interaction with other applications without completing this authentication step.
The attack requires local access to the device and exploits the service disconnection event handling. When the Keyguard service disconnects, the missing permission validation creates a window where app pinning restrictions are not properly enforced, enabling unauthorized access to other applications on the device.
Root Cause
The root cause of this vulnerability is a missing permission check in the onServiceDisconnected method of KeyguardServiceDelegate.java. When the Keyguard service disconnects, the code fails to verify that the caller has the necessary authorization to interact with apps outside the pinned application context. This insufficient access control (CWE-200) allows information disclosure through unauthorized app interactions.
Attack Vector
The attack vector is local, requiring an attacker to have physical access to the device or control over an application running on the device. The exploitation does not require user interaction or elevated privileges. An attacker could trigger the service disconnection condition and then leverage the permission gap to interact with applications that should be restricted by app pinning, potentially extracting sensitive information.
The vulnerability exploitation mechanism involves triggering a service disconnection event in the Keyguard service. When this occurs, the missing permission validation in onServiceDisconnected fails to properly enforce app pinning restrictions, allowing limited interaction with other applications. The specific information exposed depends on which apps are accessible during this window and their individual data handling practices. For technical implementation details, refer to the Android Security Bulletin 2026-03.
Detection Methods for CVE-2026-0005
Indicators of Compromise
- Unexpected Keyguard service disconnection events in system logs
- Unusual app activity or data access while device should be in pinned mode
- System log entries showing interaction with apps outside the pinned context
- Anomalous service binding/unbinding patterns in Android system services
Detection Strategies
- Monitor Android system logs for abnormal Keyguard service disconnection events
- Implement application-level logging to detect unauthorized access attempts
- Use mobile device management (MDM) solutions to monitor for unusual app interaction patterns
- Deploy behavioral analysis tools to identify potential exploitation attempts on managed devices
Monitoring Recommendations
- Enable verbose logging for Keyguard-related services on enterprise-managed devices
- Configure SIEM rules to alert on patterns indicative of app pinning bypass attempts
- Implement endpoint detection solutions capable of monitoring Android system service behavior
- Regularly audit device logs for suspicious service disconnection events
How to Mitigate CVE-2026-0005
Immediate Actions Required
- Apply the Android security patch from the March 2026 Security Bulletin immediately
- Limit physical access to devices containing sensitive information
- Consider temporarily disabling app pinning on high-value devices until patched
- Enable additional authentication mechanisms where available
Patch Information
Google has addressed this vulnerability in the Android Security Bulletin 2026-03. The patch adds the missing permission check in the onServiceDisconnected method of KeyguardServiceDelegate.java, ensuring that app pinning restrictions are properly enforced even during service disconnection events. Device manufacturers and carriers should push the March 2026 security update to affected devices running Android 14.0, 15.0, and 16.0.
Workarounds
- Implement additional authentication layers at the application level for sensitive apps
- Use enterprise mobility management (EMM) solutions to enforce additional access controls
- Restrict device usage in sensitive environments until patches are applied
- Consider using work profiles or containerization solutions to isolate sensitive data
# Verify Android security patch level on device
adb shell getprop ro.build.version.security_patch
# Expected output: 2026-03-01 or later
# Check for Keyguard service status
adb shell dumpsys activity services | grep -i keyguard
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
