CVE-2026-42955 (GCVE-0-2026-42955)
Vulnerability from cvelistv5
Published
2026-07-22 13:05
Modified
2026-07-22 14:26
CWE
  • CWE-672 - Operation on a Resource after Expiration or Release
Summary
In NLnet Labs Unbound 1.16.2 up to and including 1.25.1, a similar vulnerability as with CVE-2026-40622 in the 'ghost domain names' family of attacks was found in Unbound that could extend the ghost domain window by up to one cached TTL configured value for A/AAAA glue records. Similar to other 'ghost domain names' attacks, an adversary needs to control a (ghost) zone and be able to query a vulnerable Unbound. A single client A/AAAA query can cause Unbound to overwrite the cached expired parent-side glue rrset and essentially extend the ghost domain window by up to one cached TTL configured value ('cache-max-ttl'). In configurations where 'harden-referral-path: yes' is used (non-default configuration), no client query is required since Unbound implicitly performs that query. This is a variant of CVE-2026-40622 which only addressed the NS query.
Impacted products
Vendor Product Version
NLnet Labs Unbound Version: 1.16.2   
Create a notification for this product.
Show details on NVD website


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