{"id":"CVE-2026-42310","aliases":["GHSA-r73j-pqj5-w3x7","BIT-pillow-2026-42310","PYSEC-2026-2874"],"title":"Pillow has a PDF Parsing Trailer Infinite Loop (DoS)","summary":"Pillow has a PDF Parsing Trailer Infinite Loop (DoS)","severity":"medium","cvss":5.5,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","vendor":"pillow","product":"pillow","ecosystem":"pip","affected":["pillow >= 4.2.0, < 12.2.0"],"patched":["pillow 12.2.0"],"published":"2026-05-04","updated":"2026-09-10","sourceUpdated":"2026-09-10T03:50:55.309086884Z","source":"OSV","sourceUrl":"https://osv.dev/vulnerability/GHSA-r73j-pqj5-w3x7","references":[{"url":"https://github.com/python-pillow/Pillow/security/advisories/GHSA-r73j-pqj5-w3x7"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-42310"},{"url":"https://github.com/python-pillow/Pillow/pull/9519"},{"url":"https://github.com/python-pillow/Pillow/commit/3bf614e4b8615d0ce1d5039efaf6db447fe7c468"},{"url":"https://github.com/python-pillow/Pillow"},{"url":"https://github.com/python-pillow/Pillow/releases/tag/12.2.0"}],"tags":["osv","pip"],"epss":0.00126,"epssPercentile":0.02617,"ingestedAt":"2026-07-13T18:58:02.525Z","slug":"CVE-2026-42310","body":"## Overview\n\n### Impact\nAn attacker can supply a malicious PDF that causes the process to hang indefinitely, consuming 100% CPU and making the application unresponsive.\n\n### Patches\nPatched version: 12.2.0.\n\nPdfParser (introduced in Pillow 4.2.0) follows Prev pointers in PDF trailers to read cross-reference sections. If a\ntrailer's Prev pointer references an offset that has already been processed — either pointing to itself or forming a\nlonger cycle — the parser enters an infinite loop. Pillow now tracks previously processed trailer offsets and raises an\nerror if a cycle is detected.\n\n### Workarounds\nUse any version but the affected versions: >= 4.2.0, < 12.2.0\n\n### Resources\n - Fix: https://github.com/python-pillow/Pillow/pull/9519\n\n## Affected packages\n\n- `pillow >= 4.2.0, < 12.2.0`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `pillow 12.2.0`","depth":"sunlit","depthScore":30,"depthScoreParts":{"impact":30.3,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}