# CVE-2026-109828: libsndfile uninitialized variable in WAV parsing

Source: https://junglewise.ai/threats/cve-2026-109828-a-vulnerability-was-found-in-libsndfile-up-to-1-2-2-this-issue  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-13. Updated: 2026-10-16  
License: CC BY 4.0 with a link back

CVE-2026-109828 · Severity: medium · CVSS 4.3 · Published 2026-10-13

libsndfile is a C library used to read and write audio files in formats like WAV. A flaw in how it parses WAV file metadata allows attackers to leak uninitialized memory from the application's stack. An attacker could craft a malicious WAV file that, when opened, exposes sensitive data that was previously stored in memory.

Technologies: [Libsndfile](https://junglewise.ai/threats/technologies/libsndfile-libsndfile). Vendors: [Libsndfile](https://junglewise.ai/threats/vendors/libsndfile).

## Quick answers

**Is CVE-2026-109828 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-109828 being exploited in the wild.

**How severe is CVE-2026-109828?** Medium severity, with a CVSS score of 4.3, published 13 October 2026.

**Which products and versions are affected?** Libsndfile up to 1.2.2.

**Is there a fix for CVE-2026-109828?** 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-2026-109828 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-109828?** Check whether you run Libsndfile 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

The wavlike_subchunk_parse function in src/wavlike.c fails to initialize variables before use when parsing short 'labl' subchunks in WAV files, leading to use of uninitialized stack memory (CWE-457). Remote exploitation is possible through a crafted WAV file; no authentication or user interaction beyond opening the file is required. An attacker gains the ability to read uninitialized stack memory.

## Affected products

- libsndfile libsndfile up to 1.2.2

## Timeline

- 2026-10-13: disclosed

## References

- [https://github.com/libsndfile/libsndfile/](https://github.com/libsndfile/libsndfile/)
- [https://github.com/libsndfile/libsndfile/issues/1169](https://github.com/libsndfile/libsndfile/issues/1169)

## Related threats

- [libsndfile misaligned memory access in WAV fmt chunk parsing](https://junglewise.ai/threats/cve-2026-88386-libsndfile-1-2-2-contains-a-misaligned-memory-access-issue-in-psf)
- [libsndfile integer overflow in MAT4 file parsing](https://junglewise.ai/threats/cve-2026-88372-libsndfile-1-2-2-contains-an-integer-overflow-vulnerability-in)