CVE-2026-123603
MEDIUM
MEDIUM
Priority: 0.01
BB Relevance:
74/100
Published: 2026-11-08
Modified: 2026-11-08
First seen: 2026-11-08
Status: active
Attack Surface
Network
Low Complexity
No Auth
No Interaction
CVSS Vector Breakdown
AV:
Network
AC:
Low
PR:
None
UI:
None
S:
X
AT:
None
VC:
Low
VI:
Low
VA:
None
Description
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.
Weakness Classification (1)
Affected Software (4)
| Vendor | Product | Version |
|---|---|---|
| hickory-dns | hickory-dns | 0.25.0-alpha.3 |
| hickory-dns | hickory-dns | 0.26.0 < 0.26.2 |
| hickory-dns | hickory-dns | 0.26.0 < 0.26.2 |
| hickory-dns | hickory-dns | 0.25.0-alpha.1 < 0.26.2 |
References & Advisories (2)
vendor-advisory
third-party-advisory