{"id":"BIT-pillow-2026-96642","summary":"Pillow: TarIO negative size field causes infinite CPU-spin loop","details":"Pillow is a Python imaging library. Prior to 13.0.0, the TarIO initializer in src/PIL/TarIO.py accepts a negative octal member size and computes a backward seek that returns to the same 512-byte header. When the requested member name does not match, the parser repeatedly reads that header, consumes a full CPU core, and never returns. TarIO is reached only when an application directly uses PIL.TarIO.TarIO rather than the default Image.open() path. This issue is fixed in version 13.0.0.","aliases":["CVE-2026-96642","GHSA-3j72-p6qg-6xp7","PYSEC-2026-4341"],"modified":"2026-10-29T10:55:45.826300321Z","published":"2026-10-29T08:58:18.031Z","database_specific":{"severity":"High","cpes":["cpe:2.3:a:python:pillow:*:*:*:*:*:python:*:*"]},"references":[{"type":"FIX","url":"https://github.com/python-pillow/Pillow/commit/19b695fdcc5eddc37374e2b1645fc4185edaf71d"},{"type":"REPORT","url":"https://github.com/python-pillow/Pillow/pull/10012"},{"type":"ARTICLE","url":"https://github.com/python-pillow/Pillow/releases/tag/13.0.0"},{"type":"ADVISORY","url":"https://github.com/python-pillow/Pillow/security/advisories/GHSA-3j72-p6qg-6xp7"},{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-96642"}],"affected":[{"package":{"name":"pillow","ecosystem":"Bitnami","purl":"pkg:bitnami/pillow"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"13.0.0"}]}],"database_specific":{"source":"https://github.com/bitnami/vulndb/tree/main/data/pillow/BIT-pillow-2026-96642.json"},"severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X"}]}],"schema_version":"1.9.2"}