CVE-2026-34990

Name	CVE-2026-34990
Description	OpenPrinting CUPS is an open source printing system for Linux and other Unix-like operating systems. In versions 2.4.16 and prior, a local unprivileged user can coerce cupsd into authenticating to an attacker-controlled localhost IPP service with a reusable Authorization: Local ... token. That token is enough to drive /admin/ requests on localhost, and the attacker can combine CUPS-Create-Local-Printer with printer-is-shared=true to persist a file:///... queue even though the normal FileDevice policy rejects such URIs. Printing to that queue gives an arbitrary root file overwrite; the PoC below uses that primitive to drop a sudoers fragment and demonstrate root command execution. At time of publication, there are no publicly available patches.
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
cups (PTS)	bullseye	2.3.3op2-3+deb11u8	vulnerable
	bullseye (security)	2.3.3op2-3+deb11u10	vulnerable
	bookworm, bookworm (security)	2.4.2-3+deb12u9	vulnerable
	trixie	2.4.10-3+deb13u2	vulnerable
	trixie (security)	2.4.10-3+deb13u1	vulnerable
	forky, sid	2.4.16-1	vulnerable

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
cups	source	(unstable)	(unfixed)

Notes

[trixie] - cups <no-dsa> (Minor issue)
[bookworm] - cups <no-dsa> (Minor issue)
https://github.com/OpenPrinting/cups/security/advisories/GHSA-c54j-2vqw-wpwp