CVE-2026-40192

NameCVE-2026-40192
DescriptionPillow is a Python imaging library. Versions 10.3.0 through 12.1.1 did not limit the amount of GZIP-compressed data read when decoding a FITS image, making them vulnerable to decompression bomb attacks. A specially crafted FITS file could cause unbounded memory consumption, leading to denial of service (OOM crash or severe performance degradation). If users are unable to immediately upgrade, they should only open specific image formats, excluding FITS, as a workaround.
SourceCVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)

Vulnerable and fixed packages

The table below lists information on source packages.

Source PackageReleaseVersionStatus
pillow (PTS)bullseye8.1.2+dfsg-0.3+deb11u2fixed
bullseye (security)8.1.2+dfsg-0.3+deb11u3fixed
bookworm, bookworm (security)9.4.0-1.1+deb12u1fixed
trixie, trixie (security)11.1.0-5+deb13u1vulnerable
forky, sid12.1.1-2vulnerable

The information below is based on the following data on fixed versions.

PackageTypeReleaseFixed VersionUrgencyOriginDebian Bugs
pillowsourcebullseye(not affected)
pillowsourcebookworm(not affected)
pillowsource(unstable)(unfixed)

Notes

[bookworm] - pillow <not-affected> (Vulnerable code not present)
[bullseye] - pillow <not-affected> (Vulnerable code not present)
https://github.com/python-pillow/Pillow/security/advisories/GHSA-whj4-6x5x-4v2j
https://github.com/python-pillow/Pillow/pull/9521
Introduced with: https://github.com/python-pillow/Pillow/commit/142473c7b43a72b5dba534a26cb614b5b207ada5 (10.3.0)
Fixed by: https://github.com/python-pillow/Pillow/commit/3cb854e8b2bab43f40e342e665f9340d861aa628 (12.2.0)

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