GHSA-r73j-pqj5-w3x7MediumCVSS 5.5
Pillow has a PDF Parsing Trailer Infinite Loop (DoS)
🔗 CVE IDs covered (1)
📋 Description
Impact
An attacker can supply a malicious PDF that causes the process to hang indefinitely, consuming 100% CPU and making the application unresponsive.
Patches
Patched version: 12.2.0.
PdfParser (introduced in Pillow 4.2.0) follows Prev pointers in PDF trailers to read cross-reference sections. If a trailer's Prev pointer references an offset that has already been processed — either pointing to itself or forming a longer cycle — the parser enters an infinite loop. Pillow now tracks previously processed trailer offsets and raises an error if a cycle is detected.
Workarounds
Use any version but the affected versions: >= 4.2.0, < 12.2.0
Resources
- Fix: https://github.com/python-pillow/Pillow/pull/9519
🎯 Affected products1
- pip/pillow:>= 4.2.0, < 12.2.0
🔗 References (6)
- https://github.com/python-pillow/Pillow/security/advisories/GHSA-r73j-pqj5-w3x7
- https://github.com/python-pillow/Pillow/pull/9519
- https://nvd.nist.gov/vuln/detail/CVE-2026-42310
- https://github.com/python-pillow/Pillow/commit/3bf614e4b8615d0ce1d5039efaf6db447fe7c468
- https://github.com/python-pillow/Pillow/releases/tag/12.2.0
- https://github.com/advisories/GHSA-r73j-pqj5-w3x7