CyberRota Analysis
AI-GeneratedUnbound versions 1.16.2 through 1.25.1 are vulnerable to an attack that can extend the ghost domain window by leveraging cached A/AAAA glue records, allowing an adversary controlling a ghost zone to manipulate DNS responses. This vulnerability can be exploited without a client query in configurations with 'harden-referral-path: yes', potentially leading to DNS spoofing or cache poisoning. Organizations using affected versions of Unbound, especially those with non-default configurations, should prioritize patching to mitigate this risk.
Original NVD Description
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.
Related CVEs
Other vulnerabilities affecting the same vendor(s)