CVE-2025-48540 Overview
CVE-2025-48540 is a local out-of-bounds write vulnerability in the Android processTransactInternal function of RpcState.cpp, part of the platform's native frameworks. A logic error in this Binder RPC handling code allows a local attacker to trigger memory corruption during transaction processing. Successful exploitation leads to local privilege escalation without requiring user interaction or additional execution privileges. Google addressed the issue in the Android Security Bulletin published September 1, 2025, covering Android versions 13, 14, 15, and 16. The flaw is classified under CWE-787: Out-of-bounds Write.
Critical Impact
A local attacker with low privileges can corrupt memory in a privileged process to escalate to higher privileges on affected Android devices.
Affected Products
- Google Android 13.0
- Google Android 14.0
- Google Android 15.0 and 16.0
Discovery Timeline
- 2025-09-04 - CVE-2025-48540 published to NVD
- 2025-09-01 - Google publishes Android Security Bulletin with patches
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-48540
Vulnerability Analysis
The vulnerability resides in processTransactInternal within RpcState.cpp, a core component of Android's native Binder RPC framework in platform/frameworks/native. This code handles inbound RPC transactions and manages memory buffers used to marshal transaction data between processes. A logic error in this handler allows a crafted transaction to cause an out-of-bounds write to memory owned by the receiving process.
Because the RPC endpoint runs in a process that may hold elevated privileges, corrupting its memory provides a path to local privilege escalation. The attacker only needs the ability to send transactions to the vulnerable service from a low-privilege context on the device.
Root Cause
The root cause is a logic flaw in transaction handling within processTransactInternal, resulting in a write past the intended buffer boundary [CWE-787]. Google's fix is distributed across three commits in the AOSP frameworks/native repository (commit 570e2d6, commit 7fb4755, commit ba4ea35).
Attack Vector
Exploitation requires local access to the device and the ability to run code as a low-privilege user or app. The attacker sends a malformed RPC transaction to a service that invokes the vulnerable processTransactInternal path. No user interaction is needed. The out-of-bounds write can be shaped to modify adjacent objects or control structures, enabling escalation of privilege within the targeted native process.
Refer to the Android Security Bulletin - September 2025 for the complete technical description and affected component list.
Detection Methods for CVE-2025-48540
Indicators of Compromise
- Unexpected crashes or SIGSEGV tombstones referencing RpcState::processTransactInternal in /data/tombstones/.
- Unauthorized installation of applications or the appearance of processes running with elevated UIDs following anomalous native crashes.
- Kernel or logcat audit entries showing SELinux denials that correlate with a crashing native service.
Detection Strategies
- Monitor Android logs and crash reports for repeated native crashes in Binder RPC code paths, which may indicate exploitation attempts.
- Use mobile threat defense tooling to identify devices running Android 13, 14, 15, or 16 that lack the September 2025 security patch level.
- Correlate application install events with prior native process crashes to identify potential post-exploitation activity.
Monitoring Recommendations
- Enforce a minimum security patch level of 2025-09-01 in enterprise mobility management (EMM) compliance policies.
- Ingest Android device attestation and patch-level telemetry into the SIEM for continuous compliance monitoring.
- Review installed applications for unknown sources and revoke access from devices that fail patch-level checks.
How to Mitigate CVE-2025-48540
Immediate Actions Required
- Apply the September 2025 Android security update (patch level 2025-09-01 or later) to all managed Android 13, 14, 15, and 16 devices.
- Instruct users to install pending OEM firmware updates and reboot devices to complete patch installation.
- Block enrollment or restrict access for devices that cannot be updated to the September 2025 patch level.
Patch Information
Google released fixes in the Android Security Bulletin - September 2025. The upstream code changes are available in AOSP platform/frameworks/native in commit 570e2d6, commit 7fb4755, and commit ba4ea35. OEM delivery timing varies; confirm the security patch level in device settings after updating.
Workarounds
- No vendor-supplied workaround exists; installing the September 2025 patch is the only supported remediation.
- Restrict installation of untrusted applications through EMM policies to reduce the local attack surface until patches are applied.
- Disable sideloading and enforce Google Play Protect on managed devices to limit the ability of malicious apps to reach the vulnerable code path.
# Verify Android security patch level on a managed device
adb shell getprop ro.build.version.security_patch
# Expected output: 2025-09-01 or later
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
