CVE-2026-123603

EUVD-2026-119362
hickory-proto and hickory-resolver 0.26.0 before 0.26.2, hickory-server 0.25.0-alpha.1 before 0.26.2, and hickory-recursor 0.25.0-alpha.3 through 0.26.0-alpha.1 fail to canonicalize IPv4-mapped IPv6 addresses when checking deny_answers, deny_server, or AccessControlSet rules. Attackers can use IPv4-mapped addresses to evade answer filtering, trigger queries to denied nameservers, or reach hickory-server library deployments on dual-stack IPv6 sockets from denied clients.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
6.5 MEDIUM
NETWORK
LOW
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
Awaiting analysis
This vulnerability is currently awaiting analysis.
Base Score
CVSS 3.x
EPSS Score
Percentile: 5.83%
Debian logo
Debian Releases
Debian Product
Codename
rust-hickory-proto
forky
0.26.3-1
fixed
sid
0.26.3-1
fixed
trixie
vulnerable
rust-hickory-recursor
forky
vulnerable
sid
vulnerable
trixie
vulnerable
rust-hickory-resolver
forky
0.26.3-1
fixed
sid
0.26.3-1
fixed
trixie
vulnerable
rust-hickory-server
forky
0.26.3-1
fixed
sid
0.26.3-1
fixed
trixie
vulnerable
Common Weakness Enumeration
References
https://github.com/hickory-dns/hickory-dns/security/advisories/GHSA-4jwp-xjwm-333g
https://www.vulncheck.com/advisories/hickory-dns-missing-ipv4-mapped-ipv6-canonicalization-access-control-bypass