Is CVE-2026-97313 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-97313 being exploited in the wild.

How severe is CVE-2026-97313?

High severity, with a CVSS score of 7.5, published 21 October 2026.

Which products and versions are affected?

Isc BIND 9 9.11.3-S1 through 9.18.50-S1, 9.16.0 through 9.18.50, 9.20.0 through 9.20.29, 9.20.9-S1 through 9.20.29-S1, 9.21.0 through 9.21.26.

Is there a fix for CVE-2026-97313?

Yes: fixed in BIND 9.18.51, 9.20.30, 9.21.27. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-97313 attacked?

It is attacked over the network, in a hosted service.

Am I affected by CVE-2026-97313?

Check whether you run Isc BIND 9 at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-97313: ISC BIND recursive server assert failure denial of service

CVE-2026-97313 · Severity: high · CVSS 7.5 · Published 2026-10-21

BIND is a DNS server that many organizations rely on to translate domain names to IP addresses. A flaw in BIND's recursive query handling can cause the server to crash with an assertion failure when it receives specific sequences of DNS queries, resulting in a denial of service that disrupts DNS resolution for all clients relying on that server.

Technologies: Isc BIND 9. Vendors: Isc.

Quick answers

Is CVE-2026-97313 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-97313 being exploited in the wild.
How severe is CVE-2026-97313?: High severity, with a CVSS score of 7.5, published 21 October 2026.
Which products and versions are affected?: Isc BIND 9 9.11.3-S1 through 9.18.50-S1, 9.16.0 through 9.18.50, 9.20.0 through 9.20.29, 9.20.9-S1 through 9.20.29-S1, 9.21.0 through 9.21.26.
Is there a fix for CVE-2026-97313?: Yes: fixed in BIND 9.18.51, 9.20.30, 9.21.27. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-97313 attacked?: It is attacked over the network, in a hosted service.
Am I affected by CVE-2026-97313?: Check whether you run Isc BIND 9 at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

Fixed in: BIND 9.18.51, 9.20.30, 9.21.27

Technical details

A recursive BIND server crashes with an assertion failure when it processes a query with recursion desired (RD=1) followed by a non-recursive query (RD=0), but only if the server has at least two RPZ (Response Policy Zone) zones configured with mismatched "recursive-only" settings. The vulnerability is triggered by the specific query sequence and RPZ configuration combination, causing an unhandled assertion that terminates the server process.

Affected products

ISC BIND 9 9.11.3-S1 through 9.18.50-S1, 9.16.0 through 9.18.50, 9.20.0 through 9.20.29, 9.20.9-S1 through 9.20.29-S1, 9.21.0 through 9.21.26

Timeline

2026-10-21: disclosed
2026-10-21: patched

References

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