CVE-2026-123601 — MEDIUM (6.5)

Vulnerability Description

Hickory DNS hickory-proto 0.25.0 through 0.26.0-alpha.1 and hickory-net 0.26.0-beta.1 before 0.26.2 invert the relational operators in the wrap-around branch of find_covering_record() in nsec3.rs, so the last NSEC3 record in a zone's hash ring covers every hash except its owner. Attackers able to inject DNS responses can replay that NSEC3 record and its RRSIG to forge DNSSEC-validated negative responses denying legitimate names.

CVSS Score

6.5

MEDIUM

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H

Attack Vector

NETWORK

Attack Complexity

HIGH

Privileges Required

NONE

User Interaction

NONE

Scope

UNCHANGED

Confidentiality

NONE

Integrity

LOW

Availability

HIGH

Related Weaknesses (CWE)

CWE-480

References

FAQ

What is CVE-2026-123601?

CVE-2026-123601 is a vulnerability with a CVSS score of 6.5 (MEDIUM). Hickory DNS hickory-proto 0.25.0 through 0.26.0-alpha.1 and hickory-net 0.26.0-beta.1 before 0.26.2 invert the relational operators in the wrap-around branch of find_covering_record() in nsec3.rs, so ...

How severe is CVE-2026-123601?

CVE-2026-123601 has been rated MEDIUM with a CVSS base score of 6.5/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-123601?

Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.