CVE-2026-13204: CWE-617 Reachable Assertion in ISC BIND 9
CVE-2026-13204 is a vulnerability in ISC BIND 9 where the software may exit unexpectedly due to an assertion failure during DNSSEC validation. This occurs if a provably insecure domain is covered by both NSEC and NSEC3 records at the parent zone, but an RRSIG exists for only one of these record types. The issue affects multiple BIND 9 versions including 9.11.0 through 9.18.50, 9.20.0 through 9.20.24, 9.21.0 through 9.21.23, and their respective S1 variants. The vulnerability has a high severity with a CVSS score of 7.5 and impacts availability by causing the DNS server to exit unexpectedly.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-13204) in ISC BIND 9 involves a reachable assertion failure (CWE-617) triggered during DNSSEC proof validation. Specifically, when a domain is covered by both NSEC and NSEC3 records at the parent zone, but only one record type has an associated RRSIG, BIND may hit an assertion and exit unexpectedly. This affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.24, 9.21.0 through 9.21.23, and their S1 variants. The impact is a denial of service due to process termination. No official patch or remediation level is stated in the provided data, and no known exploits are reported in the wild.
Potential Impact
The vulnerability causes BIND 9 DNS servers to exit unexpectedly, resulting in denial of service (availability impact). There is no impact on confidentiality or integrity. This can disrupt DNS resolution services relying on the affected BIND versions.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, operators should monitor ISC advisories for updates. No temporary or official fixes are currently documented in the provided data.
CVE-2026-13204: CWE-617 Reachable Assertion in ISC BIND 9
Description
CVE-2026-13204 is a vulnerability in ISC BIND 9 where the software may exit unexpectedly due to an assertion failure during DNSSEC validation. This occurs if a provably insecure domain is covered by both NSEC and NSEC3 records at the parent zone, but an RRSIG exists for only one of these record types. The issue affects multiple BIND 9 versions including 9.11.0 through 9.18.50, 9.20.0 through 9.20.24, 9.21.0 through 9.21.23, and their respective S1 variants. The vulnerability has a high severity with a CVSS score of 7.5 and impacts availability by causing the DNS server to exit unexpectedly.
CVSS v3.1
Score 7.5high
Affected software
pkg:github/isc/bind9Run on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-13204) in ISC BIND 9 involves a reachable assertion failure (CWE-617) triggered during DNSSEC proof validation. Specifically, when a domain is covered by both NSEC and NSEC3 records at the parent zone, but only one record type has an associated RRSIG, BIND may hit an assertion and exit unexpectedly. This affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.24, 9.21.0 through 9.21.23, and their S1 variants. The impact is a denial of service due to process termination. No official patch or remediation level is stated in the provided data, and no known exploits are reported in the wild.
Potential Impact
The vulnerability causes BIND 9 DNS servers to exit unexpectedly, resulting in denial of service (availability impact). There is no impact on confidentiality or integrity. This can disrupt DNS resolution services relying on the affected BIND versions.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, operators should monitor ISC advisories for updates. No temporary or official fixes are currently documented in the provided data.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- isc
- Date Reserved
- 2026-06-24T14:12:52.934Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a60d93c9c2644c7f8363a0c
Added to database: 07/22/2026, 14:52:44 UTC
Last enriched: 07/22/2026, 15:07:30 UTC
Last updated: 07/22/2026, 16:03:01 UTC
Views: 6
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