CVE-2026-89683

Name	CVE-2026-89683
Description	In the Linux kernel, the following vulnerability has been resolved: nfsd: fix dentry ref leak on V4ROOT export filehandle lookup nfsd_set_fh_dentry() leaks the dentry reference from exportfs_decode_fh_raw() when the NFS3_FHSIZE or NFS_FHSIZE switch cases detect NFSEXP_V4ROOT and goto out. The out: label calls exp_put() but never dput(dentry), and fhp->fh_dentry was never assigned so fh_put() cannot compensate. A crafted NFSv3 filehandle targeting a V4ROOT export's fsid triggers the leak on every request.
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
linux (PTS)	bookworm	6.1.176-1	fixed
	bookworm (security)	6.1.187-1	fixed
	trixie (security), trixie	6.12.107-1	vulnerable
	forky, sid	7.1.13-1	vulnerable

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
linux	source	bookworm	(not affected)
linux	source	(unstable)	(unfixed)

[bookworm] - linux <not-affected> (Vulnerable code not present)
https://git.kernel.org/linus/6247023fbbec1325029f2d5f2a7cdc0f9f9ea15a (7.3-rc1)