Possible insecure NXDOMAIN for non-existing records under a configured island trust anchor underneath an insecure parent. (NLnet Labs Unbound)

CVE-2026-50106
MEDIUM 6.5

En bref

Source
NVD
EPSS
EPSS 0.21 % · centile 11 ()
État
PUBLISHED
Publiée
Mise à jour
Attribuée par
NLnet Labs
Statut NVD
Awaiting Analysis

Description

When NLnet Labs Unbound up to and including version 1.26.1 is configured with both a root trust anchor and an additional 'trust-anchor:' for an island-of-security zone whose parent is provably insecure under the root chain, a malicious actor who can deliver one forged NXDOMAIN response for a name inside the island, with the NSEC/SOA RRSIG 'SignerName' set to the insecure parent, tricks Unbound's validator to use the root trust anchor instead, and consecutively the insecure parent, thus causing that record to be treated as insecure and denying existence for records in the trust island.

Faiblesses (CWE)

  • CWE-807 — Reliance on Untrusted Inputs in a Security Decision

Références

Scores

VersionScoreVecteurÉvalué par
CVSS 3.1MEDIUM 6.5CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:HNLnet Labs
CVSS 3.1MEDIUM 6.5CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:HNVD · sep@nlnetlabs.nl (Secondary)

Références européennes

Produits affectés

ProduitVersions
NLnet Labs · Unboundaffected 0 < 1.26.2

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD