Pillow is a Python imaging library. From 5.1.0 until 13.0.0, Pillow can enter an infinite loop while rewriting PDF pages. PdfParser.rewrite_pages() follows Parent relationships without detecting a cycle in the page tree. An attacker can supply a cyclic PDF to an application that appends an image to that PDF. This can hold the worker at full CPU and deny service. This issue is fixed in version 13.0.0.
Fix
Patch, vendor advisory and mitigation references on NVD 2
- https://github.com/python-pillow/Pillow/commit/b3ebf20c694f2f12537a629c30229a1d5a53f777 Patch
- https://github.com/python-pillow/Pillow/security/advisories/GHSA-f2g6-542v-9j58 Exploit, Mitigation, Patch, Vendor Advisory
Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.
Change history 8
- Cpes+1 CPE criteria (now 1)NVD modified 2026-10-27 14:59
- StatusPublished → AnalyzedNVD modified 2026-10-27 14:59
- StatusUndergoing Analysis → PublishedNVD modified 2026-10-20 16:08
- StatusPublished → Undergoing AnalysisNVD modified 2026-10-20 19:50
- StatusReceived → PublishedNVD modified 2026-10-20 16:08
- StatusPublished → ReceivedNVD modified 2026-10-20 17:17
- StatusReceived → PublishedNVD modified 2026-10-19 21:31
- First seenCVSS 8.7NVD modified 2026-10-19 22:17
Affected (CPE criteria) 1
cpe:2.3:a:python:pillow:*:*:*:*:*:*:*:*
References 3
- https://github.com/python-pillow/Pillow/commit/b3ebf20c694f2f12537a629c30229a1d5a53f777 Patch
- https://github.com/python-pillow/Pillow/releases/tag/13.0.0 Release Notes
- https://github.com/python-pillow/Pillow/security/advisories/GHSA-f2g6-542v-9j58 Exploit, Mitigation, Patch, Vendor Advisory