CVE-2026-123586

Name	CVE-2026-123586
Description	Hickory DNS 0.25.0-alpha.3 through 0.25.2 contains a query amplification vulnerability in its recursive resolver, which mishandles cyclic sibling name server referrals that lack glue records. Attackers controlling two zones whose name servers reference each other without glue records can make the recursor loop, sending many upstream queries, amplified further by zero-TTL NS records.
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
rust-hickory-recursor (PTS)	trixie	0.24.1-1	vulnerable
	forky, sid	0.25.2-6	vulnerable
rust-hickory-resolver (PTS)	trixie	0.24.4-1	vulnerable
	forky, sid	0.26.3-1	fixed

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
rust-hickory-recursor	source	(unstable)	(unfixed)
rust-hickory-resolver	source	(unstable)	0.26.3-1

https://github.com/hickory-dns/hickory-dns/security/advisories/GHSA-cx5j-p54p-q756