CVE-2026-123596
Received
Received - Intake
DNSSEC Validation Flaw in Hickory DNS
Vulnerability report for CVE-2026-123596, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-11-08
Last updated on: 2026-11-08
Assigner: VulnCheck
Description
Description
Hickory DNS hickory-proto 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 NSEC handler that accepts parent-side ancestor-delegation NSEC records as proof of nonexistence for names below the zone cut. An on-path attacker, rogue parent nameserver, or attacker winning a port and TXID race can deliver one forged NXDOMAIN response built from genuinely signed parent NSEC records, causing authenticated denial of existing child-zone names cached for the negative TTL.
CVSS Scores
EPSS Scores
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| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| hickory | hickory-proto | From 0.26.0-alpha.1 (inc) |
| hickory | hickory-net | From 0.26.0-beta.1 (inc) to 0.26.2 (exc) |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-345 | The product does not sufficiently verify the origin or authenticity of data, in a way that causes it to accept invalid data. |
