If a BIND resolver is performing DNSSEC validation and encounters a maliciously crafted zone, the resolver may consume excessive CPU. Authoritative-only servers are generally unaffected, although there are circumstances where authoritative servers may make recursive queries (see: https://kb.isc.org/docs/why-does-my-authoritative-server-make-recursive-queries). This issue affects BIND 9 versions 9.11.0 through 9.16.50, 9.18.0 through 9.18.46, 9.20.0 through 9.20.20, 9.21.0 through 9.21.19, 9.11.3-S1 through 9.16.50-S1, 9.18.11-S1 through 9.18.46-S1, and 9.20.9-S1 through 9.20.20-S1.
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-1519.json
https://downloads.isc.org/isc/bind9/9.21.20
https://downloads.isc.org/isc/bind9/9.20.21
https://downloads.isc.org/isc/bind9/9.18.47
https://bugzilla.redhat.com/show_bug.cgi?id=2451305
https://access.redhat.com/security/cve/CVE-2026-1519
https://access.redhat.com/errata/RHSA-2026:8352
https://access.redhat.com/errata/RHSA-2026:8312
https://access.redhat.com/errata/RHSA-2026:8155
https://access.redhat.com/errata/RHSA-2026:8075
https://access.redhat.com/errata/RHSA-2026:7915
https://access.redhat.com/errata/RHSA-2026:6935
https://access.redhat.com/errata/RHSA-2026:34048
https://access.redhat.com/errata/RHSA-2026:29863
https://access.redhat.com/errata/RHSA-2026:29110
https://access.redhat.com/errata/RHSA-2026:25214
https://access.redhat.com/errata/RHSA-2026:25171
https://access.redhat.com/errata/RHSA-2026:25083
https://access.redhat.com/errata/RHSA-2026:24934
https://access.redhat.com/errata/RHSA-2026:24851
https://access.redhat.com/errata/RHSA-2026:24500
https://access.redhat.com/errata/RHSA-2026:16064
https://access.redhat.com/errata/RHSA-2026:16060
https://access.redhat.com/errata/RHSA-2026:15890