CVE-2025-36937: Google Android RCE Vulnerability

CVE-2025-36937 Overview

CVE-2025-36937 is an out-of-bounds write vulnerability in the AudioDecoder::HandleProduceRequest function within the audio_decoder.cc component of Google Android. The flaw stems from an incorrect bounds check during audio processing, which can be exploited remotely to achieve arbitrary code execution. This vulnerability requires no user interaction and no additional execution privileges, making it particularly dangerous for Android device users.

Critical Impact

Remote attackers can execute arbitrary code on vulnerable Android devices without user interaction or special privileges, potentially leading to complete device compromise.

Affected Products

• Google Android (all versions prior to December 2025 security patch)
• Google Pixel devices running vulnerable Android versions
• Android devices from various OEMs pending security patch deployment

Discovery Timeline

• 2025-12-11 - CVE-2025-36937 published to NVD
• 2026-01-05 - Last updated in NVD database

Technical Details for CVE-2025-36937

Vulnerability Analysis

This vulnerability is classified as CWE-787 (Out-of-bounds Write), a memory corruption flaw that occurs when software writes data past the boundaries of allocated memory buffers. In the context of AudioDecoder::HandleProduceRequest, the bounds check logic fails to properly validate input data, allowing an attacker to write beyond the intended buffer limits.

The network-accessible attack vector combined with low attack complexity makes this vulnerability particularly severe. No privileges or user interaction are required for successful exploitation, meaning an attacker could potentially craft malicious audio data that, when processed by the vulnerable decoder, triggers the out-of-bounds write condition.

Root Cause

The root cause lies in the audio_decoder.cc file where the AudioDecoder::HandleProduceRequest function performs insufficient validation of incoming data boundaries. When processing audio production requests, the function fails to properly verify that write operations remain within the allocated buffer space, leading to memory corruption when malformed or malicious input is provided.

Attack Vector

The vulnerability can be exploited over the network without requiring authentication or user interaction. An attacker could potentially deliver a specially crafted audio stream or media file that triggers the vulnerable code path in the audio decoder. When the malformed data is processed by AudioDecoder::HandleProduceRequest, the incorrect bounds check allows memory to be overwritten beyond the intended buffer, enabling arbitrary code execution with the privileges of the media processing component.

The exploitation mechanism involves:

1. Crafting malicious audio data that triggers the vulnerable code path
2. Delivering the payload to the target device via network-accessible media processing
3. Exploiting the out-of-bounds write to corrupt memory and redirect execution flow
4. Achieving remote code execution without user awareness or interaction

Detection Methods for CVE-2025-36937

Indicators of Compromise

• Unexpected crashes or restarts of the Android media framework services
• Anomalous memory allocation patterns in audio processing components
• Unusual network traffic patterns involving media streams from untrusted sources
• System log entries indicating memory corruption in audio_decoder.cc or related components

Detection Strategies

• Monitor Android system logs for crashes related to AudioDecoder or media framework components
• Implement network intrusion detection rules for anomalous audio stream characteristics
• Deploy endpoint detection solutions capable of identifying memory corruption attempts
• Analyze media processing behavior for unexpected code execution patterns

Monitoring Recommendations

• Enable verbose logging for Android media services to capture early indicators of exploitation attempts
• Implement behavioral analysis for audio processing components to detect anomalous execution patterns
• Monitor for privilege escalation attempts following media processing activities
• Configure alerts for repeated media framework crashes that may indicate exploitation attempts

How to Mitigate CVE-2025-36937

Immediate Actions Required

• Apply the December 2025 Android security patch immediately on all affected devices
• For enterprise environments, prioritize patching of Pixel devices and coordinate with OEM vendors for other Android devices
• Consider temporarily restricting access to untrusted media sources until patches are applied
• Enable Google Play Protect and ensure it is actively scanning for potential exploitation attempts

Patch Information

Google has addressed this vulnerability in the Android Security Bulletin December 2025. The patch corrects the bounds checking logic in the AudioDecoder::HandleProduceRequest function to properly validate write operations against buffer boundaries.

Organizations should apply the security patch through normal Android update mechanisms. For Pixel devices, updates are available directly from Google. Other Android device manufacturers will release patches according to their individual release schedules.

Workarounds

• Restrict network access to media processing services where possible
• Avoid processing media content from untrusted or unknown sources until patches are deployed
• Implement network segmentation to limit potential attack surface for vulnerable devices
• Consider using mobile device management (MDM) solutions to enforce security policies and expedite patch deployment