# CVE-2026-91088: GPAC heap-based buffer overflow in URL handler

Source: https://junglewise.ai/threats/cve-2026-91088-gpac-heap-based-buffer-overflow-in-url-handler  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-15. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-91088 · Severity: medium · CVSS 4.8 · Published 2026-09-15

GPAC is a multimedia framework used for video streaming and media processing. A heap-based buffer overflow vulnerability in its URL handling function could allow a local attacker to cause a crash or potentially execute arbitrary code when processing specially crafted URLs.

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

## Quick answers

**Is CVE-2026-91088 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-91088 being exploited in the wild.

**How severe is CVE-2026-91088?** Medium severity, with a CVSS score of 4.8, published 15 September 2026.

**Which products and versions are affected?** Gpac up to f1219cde.

**Is there a fix for CVE-2026-91088?** A patch was published on 2026-07-27: Patch commit afca1f1181668d85941d51ed1adf647807d5d975 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-91088 attacked?** It is attacked with local access.

**Am I affected by CVE-2026-91088?** Check whether you run Gpac 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-based buffer overflow exists in the gf_url_concatenate_ex function in utils/url.c of the URL Handler component in GPAC up to commit f1219cde. The vulnerability stems from improper bounds checking when concatenating URL strings. The attack vector is local; an attacker must provide a malicious input locally (not remotely exploitable). Successful exploitation could lead to denial of service via crash or potentially arbitrary code execution. The vulnerability has been patched in version abi-16.23 with commit afca1f1181668d85941d51ed1adf647807d5d975.

## Affected products

- GPAC GPAC up to f1219cde

## Timeline

- 2026-09-15: disclosed
- 2026-07-27: patched: Patch commit afca1f1181668d85941d51ed1adf647807d5d975

## References

- [https://github.com/gpac/gpac/](https://github.com/gpac/gpac/)
- [https://github.com/gpac/gpac/commit/afca1f1181668d85941d51ed1adf647807d5d975](https://github.com/gpac/gpac/commit/afca1f1181668d85941d51ed1adf647807d5d975)

## Related threats

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- [GPAC type confusion in gf_sg_command_apply](https://junglewise.ai/threats/cve-2026-124030-gpac-through-26-07-0-contains-a-type-confusion-vulnerability-in)
- [GPAC out-of-bounds write in AIT parser](https://junglewise.ai/threats/cve-2026-109827-a-vulnerability-has-been-found-in-gpac-up-to-26-07-0-this)
- [GPAC use after free in MP4Box filter queue](https://junglewise.ai/threats/cve-2026-108539-a-vulnerability-was-detected-in-gpac-up-to-26-07-0-this-affects)
- [GPAC buffer overflow in DASH Client URL resolution](https://junglewise.ai/threats/cve-2026-103227-a-weakness-has-been-identified-in-gpac-up-to-26-07-0-affected-by)