CVE-2026-47766

Name	CVE-2026-47766
Description	crun is an open source OCI Container Runtime fully written in C. Prior to version 1.28, crun's default device setup opens the container rootfs `/dev` directory without `O_NOFOLLOW`. If an OCI bundle contains `rootfs/dev` as a symlink and the bundle configuration does not mount `/dev`, crun follows that symlink and creates the default device nodes and stdio symlinks at the symlink target outside the container rootfs. In a local rootful crun replay, this created fixed device nodes and symlinks outside the rootfs before crun returned failure. A pre-existing file named `ptmx` in the target directory was also replaced by crun's forced `ptmx -> pts/ptmx` symlink. Version 1.28 fixes the issue.
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
crun (PTS)	bullseye	0.17+dfsg-1+deb11u2	vulnerable
	bookworm	1.8.1-1+deb12u1	vulnerable
	trixie	1.21-1	vulnerable
	forky, sid	1.28-1	fixed

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
crun	source	(unstable)	1.28-1

Notes

[trixie] - crun <no-dsa> (Minor issue)
[bookworm] - crun <no-dsa> (Minor issue)
[bullseye] - crun <postponed> (Minor issue, can be fixed with next update)
https://github.com/containers/crun/security/advisories/GHSA-7vwr-4279-7gq5
https://github.com/containers/crun/commit/c6f338ac2e26e216ab7820b91863a0b84e608097 (1.28)