NLnet Labs Unbound, up to and including version 1.16.1 is...
Moderate severity
Unreviewed
Published
Aug 2, 2022
to the GitHub Advisory Database
•
Updated Mar 29, 2023
Description
Published by the National Vulnerability Database
Aug 1, 2022
Published to the GitHub Advisory Database
Aug 2, 2022
Last updated
Mar 29, 2023
NLnet Labs Unbound, up to and including version 1.16.1 is vulnerable to a novel type of the "ghost domain names" attack. The vulnerability works by targeting an Unbound instance. Unbound is queried for a subdomain of a rogue domain name. The rogue nameserver returns delegation information for the subdomain that updates Unbound's delegation cache. This action can be repeated before expiry of the delegation information by querying Unbound for a second level subdomain which the rogue nameserver provides new delegation information. Since Unbound is a child-centric resolver, the ever-updating child delegation information can keep a rogue domain name resolvable long after revocation. From version 1.16.2 on, Unbound checks the validity of parent delegation records before using cached delegation information.
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