A recursive BIND server that receives a query with recursion desired (RD=1) followed by a non-recursive query (RD=0) may exit with an assertion failure, resulting in a denial of service. To be vulnerable, the BIND server must allow recursive queries and have at least two RPZ zones configured: one with the default setting of "recursive-only yes", and the other with "recursive-only no".
This issue affects BIND 9 versions 9.16.0 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.

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Advisories

No advisories yet.

Fixes

Solution

Upgrade to the patched release most closely related to your current version of BIND 9: 9.20.30, 9.21.27, or 9.20.30-S1.


Workaround

No workarounds known.

History

Wed, 21 Oct 2026 13:15:00 +0000

Type Values Removed Values Added
Description A recursive BIND server that receives a query with recursion desired (RD=1) followed by a non-recursive query (RD=0) may exit with an assertion failure, resulting in a denial of service. To be vulnerable, the BIND server must allow recursive queries and have at least two RPZ zones configured: one with the default setting of "recursive-only yes", and the other with "recursive-only no". This issue affects BIND 9 versions 9.16.0 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.
Title Specific RPZ configurations and query patterns may result in an unexpected exit
First Time appeared Isc
Isc bind
Weaknesses CWE-617
CPEs cpe:2.3:a:isc:bind:*:*:*:*:*:*:*:*
Vendors & Products Isc
Isc bind
References
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}


Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: isc

Published:

Updated: 2026-10-21T12:47:28.499Z

Reserved: 2026-09-24T11:09:13.016Z

Link: CVE-2026-97313

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-10-21T13:21:09.270

Modified: 2026-10-21T13:21:09.270

Link: CVE-2026-97313

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.

Weaknesses