CVE-2026-50248 (GCVE-0-2026-50248)

Vulnerability from cvelistv5 – Published: 2026-07-22 13:08 – Updated: 2026-07-22 18:58
VLAI
Title
BOGUS configured primary hostname accepted for XFR in auth/rpz zones
Summary
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.
Severity
6.5 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:L
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-22 18:58 UTC
CWE
  • CWE-345 - Insufficient Verification of Data Authenticity
Assigner
NLnet Labs CNA
CNA scorecard B 82/100 over 66 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
NLnet Labs Unbound Affected: 1.7.0 , < 1.25.2 (semver)
guessed Create a notification for this product.
Date Public
2026-07-22 00:00
Credits
Qifan Zhang (Palo Alto Networks)
Show details on NVD website
To clipboard 

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