SECURITY UPDATE: cache poisoning via unsolicited answer records
debian/patches/CVE-2025-40778.patch: require the NS RRset owner name
to be an ancestor of the queried name, restrict cached glue to the
NS bailiwick apex, and retry unsigned DNAME responses over TCP
CVE-2025-40778
SECURITY UPDATE: excessive NSEC3 iterations CPU denial of service
during insecure delegation validation
debian/patches/CVE-2026-1519.patch: cap NSEC3 iterations at
DNS_NSEC3_MAXITERATIONS (150) in isdelegation() and skip
already-trusted rdatasets during the insecurity proof