CVE-2026-50248

MEDIUM

BOGUS configured primary hostname accepted for XFR in auth/rpz zones

Title source: cna
STIX 2.1

Description

In NLnet Labs Unbound 1.7.0 up to and including 1.25.1, when an auth/rpz zone has a configured primary hostname that resolves to BOGUS A/AAAA, it is still considered as a possible XFR endpoint. A malicious actor that can spoof the hostname's A/AAAA record (no valid RRSIG required) becomes the zone's XFR primary and can replaces the entire zone/the resolver's entire response policy.

References (1)

Core 1
Core References

Scores

CVSS v3 6.5
EPSS 0.0013
EPSS Percentile 2.8%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:L

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-345
Status published
Products (2)
NLnet Labs/Unbound 1.7.0 - 1.25.2
nlnetlabs/unbound 1.7.0 - 1.25.2
Published Jul 22, 2026
Tracked Since Jul 22, 2026