Heap Buffer Overflow in ESP32-audioI2S AudioBuffer

Executive Summary

This is a heap-based buffer overflow in the ESP32-audioI2S library version 3.4.5. The vulnerability occurs in the AudioBuffer::writeSpace() function where a memcpy operation copies a fixed number of bytes without checking available space in the ring buffer. When the read pointer reaches the buffer end, it causes out-of-bounds writes that corrupt adjacent heap memory including PSRAM metadata on ESP32 devices.

Useful 0 Not Useful 0

Detection Guidance

Detect this vulnerability by monitoring ESP32 devices running ESP32-audioI2S 3.4.5 for crashes during audio playback, especially with long streams or crafted media files. Use AddressSanitizer builds to catch heap buffer overflows during runtime. Check for watchdog reboots or audio playback freezes as potential indicators.

Useful 0 Not Useful 0

Impact Analysis

The primary impact is remote denial of service causing ESP32 watchdog reboots or audio playback freezes. Secondary impacts include heap metadata corruption that could enable remote arbitrary code execution and potential data leaks. Exploitation requires only loading untrusted audio media on the target device without authentication or special hardware.

Useful 0 Not Useful 0

Compliance Impact

This vulnerability primarily causes remote denial of service or audio playback freezes on ESP32 devices, which does not directly impact GDPR or HIPAA compliance. However, if exploited for arbitrary code execution or data leaks, it could potentially lead to unauthorized access to personal or sensitive data, violating GDPR or HIPAA requirements for data protection and integrity.

Useful 0 Not Useful 0

Mitigation Strategies

Immediately stop using ESP32-audioI2S 3.4.5. Monitor network traffic for untrusted audio media files. Implement strict input validation for audio streams. Consider isolating affected devices from critical systems until a patch is available. No official patch exists yet, so mitigation requires avoiding the vulnerable version.

Useful 0 Not Useful 0