CVE-2025-48654 Overview
CVE-2025-48654 is a local privilege escalation vulnerability in the Android CompanionDeviceManagerService. The flaw resides in the onStart method of CompanionDeviceManagerService.java and stems from a logic error that creates a confused deputy condition [CWE-610]. A local attacker with low privileges can exploit this issue to elevate privileges without user interaction and without requiring additional execution privileges. The vulnerability affects Google Android 16.0, including QPR2 Beta 1, Beta 2, and Beta 3 builds. Google addressed the issue in the March 2026 Android Security Bulletin.
Critical Impact
Local attackers can escalate privileges on affected Android 16.0 devices without user interaction, gaining elevated access to companion device management functions.
Affected Products
- Google Android 16.0
- Google Android 16.0 QPR2 Beta 1, Beta 2, Beta 3
- Devices running affected Android builds via the CompanionDeviceManagerService component
Discovery Timeline
- 2026-03-02 - CVE-2025-48654 published to NVD
- 2026-03-06 - Last updated in NVD database
- 2026-03-01 - Addressed in the Android Security Bulletin March 2026
Technical Details for CVE-2025-48654
Vulnerability Analysis
The vulnerability is a local privilege escalation in the onStart method of CompanionDeviceManagerService.java. The CompanionDeviceManagerService is a system service that manages companion device associations such as smartwatches and fitness trackers. A logic error in onStart allows a low-privileged local process to coerce the privileged service into performing actions on its behalf, creating a confused deputy scenario [CWE-610].
The attack requires only local access and low privileges. User interaction is not required. Successful exploitation allows an unprivileged application to perform operations reserved for higher-privileged contexts, leading to elevation of privilege within the Android security model.
Root Cause
The root cause is a logic error in the service initialization path. The onStart handler does not correctly validate the identity or privileges of the requesting principal before acting on inputs, allowing a less privileged caller to influence privileged operations. This pattern matches CWE-610 (Externally Controlled Reference to a Resource in Another Sphere).
Attack Vector
An attacker must have a local foothold on the device, typically through a malicious or compromised application installed on the target. The malicious app interacts with CompanionDeviceManagerService through standard Binder IPC and triggers the flawed code path in onStart. Because no user interaction is required, exploitation can occur silently in the background after app installation.
No public proof-of-concept code is available. Refer to the Android Security Bulletin March 2026 for vendor-supplied technical details and patch references.
Detection Methods for CVE-2025-48654
Indicators of Compromise
- Unexpected companion device association events recorded by CompanionDeviceManagerService in logcat from non-privileged applications.
- Applications without companion device permissions invoking Binder calls targeting the companion device manager.
- Anomalous process behavior where third-party applications gain access to system-level resources or APIs.
Detection Strategies
- Inspect Android system logs for invocations of CompanionDeviceManagerService.onStart originating from non-system UIDs.
- Use Mobile Threat Defense (MTD) tooling to flag installed applications requesting or abusing companion device APIs without legitimate use cases.
- Correlate application install events with subsequent privilege-sensitive operations to identify suspicious sequences.
Monitoring Recommendations
- Track Android build fingerprints across the fleet and prioritize patching devices on Android 16.0 base and QPR2 Beta builds.
- Monitor enterprise mobility management (EMM) telemetry for sideloaded applications and applications from untrusted sources.
- Audit application permission grants and Binder IPC patterns where supported by mobile EDR agents.
How to Mitigate CVE-2025-48654
Immediate Actions Required
- Apply the March 2026 Android security patch level (2026-03-01 or later) on all affected devices.
- Inventory devices on Android 16.0, including QPR2 Beta builds, and prioritize them for update deployment via mobile device management (MDM).
- Restrict installation of applications to vetted sources and block sideloading on managed devices.
- Remove Android 16.0 QPR2 Beta builds from production fleets until updated.
Patch Information
Google released the fix in the Android Security Bulletin March 2026. Devices must be updated to a security patch level of 2026-03-01 or later. OEMs distribute the patch through their respective firmware update channels, and timing varies by device manufacturer and carrier.
Workarounds
- No official vendor workaround is published. Patching is the recommended remediation.
- Limit exposure by enforcing application allowlisting through MDM until devices receive the patch.
- Disable or restrict use of companion device features on high-risk devices where feasible.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
