# CVE-2026-51244: schreibfaul1 ESP32-audioI2S heap buffer overflow in UnpackFrameHeader

Source: https://junglewise.ai/threats/cve-2026-51244-schreibfaul1-esp32-audioi2s-heap-buffer-overflow-in  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-27. Updated: 2026-07-27  
License: CC BY 4.0 with a link back

CVE-2026-51244 · Severity: high · CVSS 7.5 · Published 2026-07-27

A vulnerability exists in the ESP32-audioI2S library, which is used by ESP32 microcontrollers to play audio files. By providing a specially crafted MP3 file, an attacker can cause the device to crash or potentially run unauthorized code. This could lead to a permanent service outage or allow an attacker to gain control over the connected hardware.

Technologies: [Schreibfaul1 ESP32-audioI2S](https://junglewise.ai/threats/technologies/esp32-audioi2s). Vendors: [Schreibfaul1](https://junglewise.ai/threats/vendors/schreibfaul1).

## Quick answers

**Is CVE-2026-51244 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-51244 being exploited in the wild.

**How severe is CVE-2026-51244?** High severity, with a CVSS score of 7.5, published 27 July 2026.

**Which products and versions are affected?** Schreibfaul1 ESP32-audioI2S 3.4.5.

**Is there a fix for CVE-2026-51244?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-51244 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-51244?** Check whether you run Schreibfaul1 ESP32-audioI2S at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A heap buffer overflow exists in the UnpackFrameHeader() function within the MP3 decoder of ESP32-audioI2S version 3.4.5. The vulnerability is caused by the lack of boundary validation for m_MPEGVersion and srIdx values parsed directly from the MP3 bitstream. These unvalidated indices are used to access the static sfBandTable, resulting in out-of-bounds memory access. An attacker can provide a malicious MP3 file that, when processed, leads to corrupted pointers and subsequent out-of-bounds heap writes, potentially allowing for arbitrary code execution or a denial-of-service (DoS) on the ESP32 hardware.

## Affected products

- schreibfaul1 ESP32-audioI2S 3.4.5

## Timeline

- 2026-07-27: advisory: CVE published by NVD/MITRE

## References

- [https://github.com/programmervuln/cveadvisory-/blob/main/CVE-2026-51244](https://github.com/programmervuln/cveadvisory-/blob/main/CVE-2026-51244)
- [https://github.com/schreibfaul1/ESP32-audioI2S/blob/master/src/mp3_decoder/mp3_decoder.cpp](https://github.com/schreibfaul1/ESP32-audioI2S/blob/master/src/mp3_decoder/mp3_decoder.cpp)

## Related threats

- [ESP32-audioI2S heap out-of-bounds read in ID3 header processing](https://junglewise.ai/threats/cve-2026-87961-esp32-audioi2s-heap-out-of-bounds-read-in-id3-header-processing)
- [schreibfaul1 ESP32-audioI2S heap overflow in latinToUTF8](https://junglewise.ai/threats/cve-2026-51272-schreibfaul1-esp32-audioi2s-heap-overflow-in-latintoutf8)
- [schreibfaul1 ESP32-audioI2S heap buffer overflow in ID3v2 APIC parsing](https://junglewise.ai/threats/cve-2026-51275-schreibfaul1-esp32-audioi2s-heap-buffer-overflow-in-id3v2-apic)
- [schreibfaul1 ESP32-audioI2S heap overflow in SYLT parser](https://junglewise.ai/threats/cve-2026-51274-schreibfaul1-esp32-audioi2s-heap-overflow-in-sylt-parser)
- [schreibfaul1 ESP32-audioI2S heap overflow in showID3Tag](https://junglewise.ai/threats/cve-2026-51273-schreibfaul1-esp32-audioi2s-heap-overflow-in-showid3tag)