{"id":"CVE-2026-112406","title":"Pillow: Infinite loop in PdfParser.rewrite_pages on page tree Parent cycle","summary":"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 …","severity":"high","cvss":8.7,"cvssVector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","cvssSource":"cna","cwe":["CWE-835"],"vendor":"python-pillow","product":"Pillow","affected":["Pillow >= 5.1.0, < 13.0.0"],"published":"2026-10-19","updated":"2026-10-19","sourceUpdated":"2026-10-19T21:31:49.946Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-112406","references":[{"url":"https://github.com/python-pillow/Pillow/security/advisories/GHSA-f2g6-542v-9j58","label":"https://github.com/python-pillow/Pillow/security/advisories/GHSA-f2g6-542v-9j58"},{"url":"https://github.com/python-pillow/Pillow/commit/b3ebf20c694f2f12537a629c30229a1d5a53f777","label":"https://github.com/python-pillow/Pillow/commit/b3ebf20c694f2f12537a629c30229a1d5a53f777"},{"url":"https://github.com/python-pillow/Pillow/releases/tag/13.0.0","label":"https://github.com/python-pillow/Pillow/releases/tag/13.0.0"}],"tags":["cve.org"],"ingestedAt":"2026-10-19T21:43:56.114Z","slug":"CVE-2026-112406","body":"## Overview\n\nPillow 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.\n\n## Affected\n\n- `Pillow >= 5.1.0, < 13.0.0`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":48,"depthScoreParts":{"impact":47.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}