CVE-2026-112399

Name	CVE-2026-112399
Description	Pillow is a Python imaging library. From 8.1.0 until 13.0.0, Pillow can allocate an APNG disposal background at the full canvas size before applying the decompression-bomb check. A crafted APNG with a small first frame, a very large declared canvas, and background disposal or first-frame OP_PREVIOUS reaches PngImageFile._seek while Image.open() positions frame zero. The full-canvas allocation occurs inside Image.open() without requiring pixel loading or frame iteration. This can exhaust memory and deny service. This issue is fixed in version 13.0.0.
Source	CVE (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 Package	Release	Version	Status
pillow (PTS)	bookworm, bookworm (security)	9.4.0-1.1+deb12u1	vulnerable
	trixie	11.1.0-5+deb13u4	vulnerable
	trixie (security)	11.1.0-5+deb13u3	vulnerable
	forky, sid	12.3.0-1	vulnerable

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
pillow	source	(unstable)	13.0.0-1

Notes

https://github.com/python-pillow/Pillow/security/advisories/GHSA-5xm2-6676-qcp9
Fixed by: https://github.com/python-pillow/Pillow/commit/f1acfc54c53502948d0d14121872061df931db48 (13.0.0)