Pillow: Quadratic GIF comment copying during save
On Pillow 12.3.0 and upstream `main` (`ad277e2761b489681e71b51e91367d46b0ceabb9`), a GIF with a long comment makes `_get_global_header()` copy portions of the comment repeatedly when saving, including comments carried over from untrusted images. I suggest provisional **Moderate** severity for crafted-image CPU denial of service, with CVSS-B 6.9 assuming a network service automatically opens unauthenticated uploads and they are resaved as GIFs; impact depends on input-size, concurrency, and worker CPU limits.
describes (1)
Related CVEs.
| ID | severity | exploitable | ||
|---|---|---|---|---|
| CVE-2026-112891US | high7.5 | — | ||
Pillow is a Python imaging library. From 9.2.0 until 13.0.0, Pillow performs quadratic copying when saving a GIF with a long comment. _get_global_header() repeatedly copies portion… | ||||
references
External citations — patches, advisories, analysis.
- https://github.com/python-pillow/PillowPACKAGE
- https://github.com/python-pillow/Pillow/commit/68a3fe957d8a4d552e8c69d96066d749f0614c7eWEB
- https://github.com/python-pillow/Pillow/releases/tag/13.0.0WEB
- https://github.com/python-pillow/Pillow/security/advisories/GHSA-fc9g-5qg7-mf45WEB
- https://nvd.nist.gov/vuln/detail/CVE-2026-112891ADVISORY
Advisories like this name the exposed products attackers go after on your perimeter. See what is exposed on your perimeter with a free passive scan.
Free scan