CVE-2025-48563 Overview
CVE-2025-48563 is a local privilege escalation vulnerability in the Android platform. The flaw resides in the onNullBinding method of RemoteFillService.java, part of the Autofill framework. An insecure default value allows a background activity launch that bypasses Android's foreground activity restrictions. A local attacker with low privileges can escalate to higher privileges without user interaction. The issue affects Android versions 13, 14, 15, and 16. Google addressed the vulnerability in the September 2025 Android Security Bulletin.
Critical Impact
Local applications can escalate privileges by launching background activities through the Autofill service without user consent or additional execution privileges.
Affected Products
- Google Android 13.0
- Google Android 14.0
- Google Android 15.0 and 16.0
Discovery Timeline
- 2025-09-04 - CVE-2025-48563 published to NVD
- 2025-09-01 - Google releases fix in Android Security Bulletin
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-48563
Vulnerability Analysis
The vulnerability exists in Android's RemoteFillService, a system component that mediates communication between the Autofill framework and third-party autofill provider services. When a bound Autofill provider returns a null binding, the onNullBinding callback executes with an insecure default configuration. This default permits background activity launches that Android normally restricts through its background activity launch (BAL) policy.
A malicious local application registered as an autofill provider can trigger the null binding path. The service then launches activities from the background, effectively bypassing user-visible foreground state checks. The result is local escalation of privilege classified under [CWE-453] Insecure Default Variable Initialization.
Root Cause
The root cause is an insecure default value in the option flags passed during the null binding callback. Android's background activity launch restrictions rely on the caller providing conservative defaults. The RemoteFillService initialization path did not enforce these defaults, granting the launched component permissions it should not have received.
Attack Vector
Exploitation requires local access with low privileges (AV:L/PR:L). An attacker installs a malicious application that registers as an autofill service or interacts with the autofill flow. By forcing a null binding response, the attacker triggers the vulnerable code path. No user interaction is required. Refer to the Android Source Code Change for the specific patched logic.
Detection Methods for CVE-2025-48563
Indicators of Compromise
- Applications registering as autofill providers without a legitimate autofill user interface or business purpose.
- Unexpected activity launches originating from android.service.autofill.AutofillService bindings while the device is idle or the source app is backgrounded.
- System log entries in logcat referencing RemoteFillService null bindings followed by activity starts from non-foreground processes.
Detection Strategies
- Inventory installed autofill providers on managed Android fleets and flag providers not on an approved list.
- Monitor mobile threat defense telemetry for privilege escalation patterns tied to system service bindings.
- Correlate Android platform logs with process activity to identify background activity launches following autofill service binding events.
Monitoring Recommendations
- Enroll devices in an MDM or mobile threat defense solution that reports Android security patch level and flags devices below the September 2025 patch level.
- Alert on installation of new autofill provider apps outside enterprise app catalogs.
- Track exploitation research and updates in the Android Security Bulletin September 2025.
How to Mitigate CVE-2025-48563
Immediate Actions Required
- Apply the September 2025 Android security patch level (2025-09-01 or later) to all supported devices.
- Audit installed autofill providers and remove any that are unnecessary or untrusted.
- Restrict sideloading of applications on managed devices through MDM policy.
Patch Information
Google published the fix in the Android Security Bulletin September 2025. The corresponding platform change is available in the Android Open Source Project commit. Device manufacturers integrate the fix into their monthly security update rollouts. Verify device patch level under Settings > About phone > Android security update.
Workarounds
- Disable the Autofill service on devices where autofill is not required by setting the autofill provider to None in system settings.
- Enforce enterprise policies that block installation of unapproved autofill providers via DevicePolicyManager controls.
- Prioritize update deployment for devices running Android 13 through 16 that have not yet received the September 2025 patch.
# Verify Android security patch level on a device via ADB
adb shell getprop ro.build.version.security_patch
# Expected output for patched devices: 2025-09-01 or later
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
