Red Hat Security Advisory: bind security, bug fix, and enhancement update
🔗 CVE IDs covered (3)
📋 Description
CVE-2026-19630 — bind: BIND: Denial of Service via unbounded processing of crafted DNS messages CVE-2026-19662 — bind9: bind: BIND 9: Denial of Service via crafted DNSSEC responses CVE-2026-94300 — bind: bind: Arbitrary code execution via GSS-TSIG UDP message replay
🎯 Affected products173
- Red Hat Enterprise Linux AppStream (v. 8)
- Red Hat Enterprise Linux BaseOS (v. 8)
- bind-32:9.11.36-18.el8_10.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 8)
- bind-32:9.11.36-18.el8_10.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 8)
- bind-32:9.11.36-18.el8_10.s390x as a component of Red Hat Enterprise Linux AppStream (v. 8)
- bind-32:9.11.36-18.el8_10.src as a component of Red Hat Enterprise Linux BaseOS (v. 8)
- bind-32:9.11.36-18.el8_10.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 8)
- bind-chroot-32:9.11.36-18.el8_10.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 8)
- bind-chroot-32:9.11.36-18.el8_10.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 8)
- bind-chroot-32:9.11.36-18.el8_10.s390x as a component of Red Hat Enterprise Linux AppStream (v. 8)
- bind-chroot-32:9.11.36-18.el8_10.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 8)
- bind-debuginfo-32:9.11.36-18.el8_10.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 8)
- bind-debuginfo-32:9.11.36-18.el8_10.aarch64 as a component of Red Hat Enterprise Linux BaseOS (v. 8)
- bind-debuginfo-32:9.11.36-18.el8_10.i686 as a component of Red Hat Enterprise Linux AppStream (v. 8)
- bind-debuginfo-32:9.11.36-18.el8_10.i686 as a component of Red Hat Enterprise Linux BaseOS (v. 8)
- bind-debuginfo-32:9.11.36-18.el8_10.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 8)
- bind-debuginfo-32:9.11.36-18.el8_10.ppc64le as a component of Red Hat Enterprise Linux BaseOS (v. 8)
- bind-debuginfo-32:9.11.36-18.el8_10.s390x as a component of Red Hat Enterprise Linux AppStream (v. 8)
- bind-debuginfo-32:9.11.36-18.el8_10.s390x as a component of Red Hat Enterprise Linux BaseOS (v. 8)
- bind-debuginfo-32:9.11.36-18.el8_10.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 8)
- bind-debuginfo-32:9.11.36-18.el8_10.x86_64 as a component of Red Hat Enterprise Linux BaseOS (v. 8)
- bind-debugsource-32:9.11.36-18.el8_10.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 8)
- bind-debugsource-32:9.11.36-18.el8_10.aarch64 as a component of Red Hat Enterprise Linux BaseOS (v. 8)
- bind-debugsource-32:9.11.36-18.el8_10.i686 as a component of Red Hat Enterprise Linux AppStream (v. 8)
- bind-debugsource-32:9.11.36-18.el8_10.i686 as a component of Red Hat Enterprise Linux BaseOS (v. 8)
- bind-debugsource-32:9.11.36-18.el8_10.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 8)
- bind-debugsource-32:9.11.36-18.el8_10.ppc64le as a component of Red Hat Enterprise Linux BaseOS (v. 8)
- bind-debugsource-32:9.11.36-18.el8_10.s390x as a component of Red Hat Enterprise Linux AppStream (v. 8)
- bind-debugsource-32:9.11.36-18.el8_10.s390x as a component of Red Hat Enterprise Linux BaseOS (v. 8)
- bind-debugsource-32:9.11.36-18.el8_10.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 8)
- +143 more not shown
✅ Remediation
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 Workaround: To mitigate this issue, consider disabling DNSSEC validation on `named` resolvers if it is not a strict requirement for your environment. This can be achieved by setting `dnssec-validation no;` in the `named.conf` file. Disabling DNSSEC validation will prevent the resolver from processing DNSSEC-signed zones, thereby avoiding this specific vulnerability, but it will also remove the security benefits provided by DNSSEC. After modifying the configuration, the `named` service must be reloaded or restarted for the changes to take effect. `sudo systemctl reload named` `sudo systemctl restart named` Workaround: Disable GSS-TSIG in the BIND configuration if Kerberos-authenticated dynamic DNS functionality is not required, or restrict network access to the DNS service using firewall controls. To disable GSS-TSIG, comment out or remove the `tkey-gssapi-keytab` and `tkey-gssapi-credential` directives within `/etc/named.conf` (and any referenced include files), then restart the service: systemctl restart named If operating named inside a chroot environment, execute: systemctl restart named-chroot Alternatively, restrict UDP and TCP traffic on port 53 to trusted network segments using host or network firewalls to block untrusted external access. Caveats: Disabling GSS-TSIG prevents clients from performing Kerberos-authenticated dynamic DNS modifications, which may disrupt environments relying on automated Active Directory or Identity Management (IdM) enrollment. Warning: Restarting the BIND service will momentarily interrupt active DNS query processing and domain name resolution for dependent network clients.
🔗 References (6)
- selfhttps://access.redhat.com/errata/RHSA-2026:93925
- externalhttps://access.redhat.com/security/updates/classification/#important
- externalhttps://bugzilla.redhat.com/show_bug.cgi?id=2535445
- externalhttps://bugzilla.redhat.com/show_bug.cgi?id=2556406
- externalhttps://bugzilla.redhat.com/show_bug.cgi?id=2556407
- selfhttps://security.access.redhat.com/data/csaf/v2/advisories/2026/rhsa-2026_93925.json