# CVE-2025-55661: GPAC MP4Box heap buffer overflow in Opus audio stream parser

Source: https://junglewise.ai/threats/cve-2025-55661-gpac-mp4box-heap-buffer-overflow-in-opus-audio-stream-parser  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-06-15. Updated: 2026-06-15  
License: CC BY 4.0 with a link back

CVE-2025-55661 · Severity: info · CVSS 0 · Published 2026-06-15

GPAC MP4Box is a popular multimedia packager used to process and convert video and audio files. A vulnerability in how it handles Opus audio streams allows an attacker to crash the application by providing a specially crafted MP4 file. This could disrupt media processing workflows or automated video conversion services.

Technologies: [Gpac MP4Box](https://junglewise.ai/threats/technologies/mp4box). Vendors: [Gpac](https://junglewise.ai/threats/vendors/gpac).

## Quick answers

**Is CVE-2025-55661 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2025-55661 being exploited in the wild.

**How severe is CVE-2025-55661?** Informational severity, with a CVSS score of 0, published 15 June 2026.

**Which products and versions are affected?** Gpac MP4Box 2.4.

**Is there a fix for CVE-2025-55661?** 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-2025-55661 attacked?** It is attacked with local access, in a software library.

**Am I affected by CVE-2025-55661?** Check whether you run Gpac MP4Box 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 vulnerability exists in the Opus audio stream parser of GPAC MP4Box version 2.4. The flaw is triggered when the application processes a maliciously crafted MP4 file containing Opus audio data. An attacker can exploit this by inducing a user or automated system to open the file, leading to memory corruption and a subsequent application crash (Denial of Service). The vulnerability is local in nature as it requires the processing of a specific file. No official patch details were provided in the initial advisory, though users are advised to exercise caution with untrusted media files.

## Affected products

- GPAC MP4Box 2.4

## Timeline

- 2026-06-15: disclosed: CVE published to NVD

## References

- [https://infosec.exchange/@sigdevel/116733907390103029](https://infosec.exchange/@sigdevel/116733907390103029)

## Related threats

- [GPAC MP4Box segmentation fault in dump_isom_saps](https://junglewise.ai/threats/cve-2025-55667-a-segmentation-violation-in-the-dump-isom-saps-function-mp4box)
- [GPAC MP4Box use-after-free in gf_filter_pid_get_packet](https://junglewise.ai/threats/cve-2025-55654-a-use-after-free-in-the-gf-filter-pid-get-packet-function-filter)
- [GPAC MP4Box floating point exception in gf_parse_lfrac](https://junglewise.ai/threats/cve-2025-55653-gpac-mp4box-v2-4-was-discovered-to-contain-a-floating-point)
- [GPAC MP4Box heap buffer overflow in stbl_AddSize](https://junglewise.ai/threats/cve-2025-55640-a-heap-buffer-overflow-in-the-stbl-addsize-function-isomedia-stbl)
- [GPAC MP4Box use-after-free in gf_node_deactivate_ex](https://junglewise.ai/threats/cve-2026-90827-gpac-mp4box-use-after-free-in-gf-node-deactivate-ex)