CVE-2026-81642

Name	CVE-2026-81642
Description	In NLnet Labs Unbound up to and including 1.26.0, a vulnerability was found in the DNSSEC validator that enables denial of service and possible remote code execution as a result of digesting DNSKEYs. A DNSKEY with an owner compression pointer to its own RDATA can overflow the digest buffer. Remote code execution is possible through attacker controlled data. An adversary can exploit the vulnerability by controlling a malicious zone and querying a vulnerable Unbound.
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)
References	DSA-6507-1

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
unbound (PTS)	bookworm	1.17.1-2+deb12u4	vulnerable
	bookworm (security)	1.17.1-2+deb12u3	vulnerable
	trixie	1.22.0-2+deb13u3	vulnerable
	trixie (security)	1.26.1-0+deb13u1	fixed
	forky, sid	1.26.1-1	fixed

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
unbound	source	trixie	1.26.1-0+deb13u1		DSA-6507-1
unbound	source	(unstable)	1.26.1-1

https://nlnetlabs.nl/downloads/unbound/CVE-2026-81642.txt