Cve 2026 80274

If a BIND resolver sends a query for a DNSSEC-signed authoritative zone, and the authoritative server replies with a valid wildcard answer and signed NSEC3 proof, followed by an unsigned NSEC at the same owner name, it will trigger an unexpected program exit.

A successful attack could cause an unexpected program exit and denial-of-service.

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

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No workarounds known.

We are not aware of any active exploits.

Upgrade to the patched release most closely related to your current version of BIND 9:

BIND Supported Preview Edition is a special feature preview branch of BIND provided to eligible ISC support customers.

ISC would like to thank hythyt for bringing this vulnerability to our attention.

Document revision history:

1.0 Early Notification, 9 September 2026

1.1 Revised the list of fixed versions, 11 September 2026

2.0 Public disclosure, 16 September 2026

See our BIND 9 Security Vulnerability Matrix for a complete listing of security vulnerabilities and versions affected.

Do you still have questions?

Questions regarding this advisory should be posted as confidential GitLab issues at:

ISC patches only currently supported versions. When possible we indicate EOL versions affected. For current information on which versions are actively supported, please see .

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