{"id":"GHSA-fc9g-5qg7-mf45","summary":"Pillow: Quadratic GIF comment copying during save","details":"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.","aliases":["CVE-2026-112891"],"modified":"2026-10-21T20:45:04.633756568Z","published":"2026-10-21T20:38:43Z","database_specific":{"cwe_ids":["CWE-407"],"severity":"MODERATE","github_reviewed":true,"github_reviewed_at":"2026-10-21T20:38:43Z","nvd_published_at":"2026-10-19T22:17:08Z"},"references":[{"type":"WEB","url":"https://github.com/python-pillow/Pillow/security/advisories/GHSA-fc9g-5qg7-mf45"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-112891"},{"type":"WEB","url":"https://github.com/python-pillow/Pillow/commit/68a3fe957d8a4d552e8c69d96066d749f0614c7e"},{"type":"PACKAGE","url":"https://github.com/python-pillow/Pillow"},{"type":"WEB","url":"https://github.com/python-pillow/Pillow/releases/tag/13.0.0"}],"affected":[{"package":{"name":"pillow","ecosystem":"PyPI","purl":"pkg:pypi/pillow"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"9.2.0"},{"fixed":"13.0.0"}]}],"versions":["10.0.0","10.0.1","10.1.0","10.2.0","10.3.0","10.4.0","11.0.0","11.1.0","11.2.1","11.3.0","12.0.0","12.1.0","12.1.1","12.2.0","12.3.0","9.2.0","9.3.0","9.4.0","9.5.0"],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/10/GHSA-fc9g-5qg7-mf45/GHSA-fc9g-5qg7-mf45.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N"}]}