CVE-2026-123595
Hickory DNS through 0.26.0-alpha.1 DNSSEC Validation Bypass via Ancestor-Delegation NSEC3
CVSS Score
8.8
EPSS Score
0.0%
EPSS Percentile
0th
Hickory DNS hickory-proto 0.25 through 0.26.0-alpha.1 and hickory-net 0.26.0-beta.1 before 0.26.2 contain a DNSSEC validation flaw in the validating recursor's NSEC3 handler, which matches the closest encloser by hash alone without checking the type bitmap and so accepts parent-side ancestor-delegation NSEC3 records as proof of nonexistence. An attacker who delivers one response built from genuinely signed parent NSEC3 records can cause NXDOMAIN or NODATA to be cached with AD=1, denying resolution of existing names at and below the zone cut.
| CWE | CWE-345 |
| Vendor | hickory-dns |
| Product | hickory-dns |
| Published | Nov 8, 2026 |
Stay Ahead of the Next One
Get instant alerts for hickory-dns hickory-dns
Be the first to know when new high vulnerabilities affecting hickory-dns hickory-dns are published — delivered to Slack, Telegram or Discord.
Get Free Alerts →
Free · No credit card · 60 sec setup
CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
Affected Versions
hickory-dns / hickory-dns
0.25 ≤ 0.26.0-alpha.1
hickory-dns / hickory-dns
0.26.0-beta.1 < 0.26.2
References
Credits
🔍 qifan-sailboat