Vulnerability in ISC BIND 9

[ Description ]Official description

In a BIND resolver, inbound DNS protocol messages with a particular structure will result in additional processing, with no limit imposed by BIND. A DNS message with a maliciously large number of such structures will cause BIND to consume disproportionate amounts of CPU time and memory during processing. This issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.29, 9.21.0 through 9.21.26, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.29-S1.

[ Fixes ]Fixes and patches

No fix or interim patch is linked from our sources yet. Check the vendor references below and limit exposure of affected systems until a fix is available.

[ Advisories ]Government CERT advisories

• BSI CERT-Bund21 Oct 2026WID-SEC-2026-4116

  Internet Systems Consortium BIND: Multiple vulnerabilities Translated from German

  Risk highCVE-2026-94300CVE-2026-97313CVE-2026-96888+1 more CVEs

[ References ]References

• downloads.isc.org/isc/bind9/9.20.30
• downloads.isc.org/isc/bind9/9.21.27
• kb.isc.org/docs/cve-2026-19630