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CVE-2026-80274: CWE-617 Reachable Assertion in ISC BIND 9

0
High
VulnerabilityCVE-2026-80274cvecve-2026-80274cwe-617
Published: 09/16/2026 (09/16/2026, 14:07:20 UTC)
Source: CVE Database V5
Vendor/Project: ISC
Product: BIND 9

Description

CVE-2026-80274 is a high-severity vulnerability in ISC BIND 9 DNS software that causes the program to exit unexpectedly when a resolver receives a specific sequence of DNSSEC-signed responses involving wildcard answers and NSEC/NSEC3 proofs. This affects multiple BIND 9 versions from 9.11.0 through 9.21.25 and their S1 variants. The vulnerability results in denial of service due to an assertion failure.

CVSS v3.1

Score 7.5high

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected software

ISC

BIND 9

Affected versions
>=9.11.0 <=9.18.50>=9.20.0 <=9.20.27>=9.21.0 <=9.21.25>=9.11.3-S1 <=9.18.50-S1>=9.20.9-S1 <=9.20.27-S1
GitHub Actionsmore threats →ai
isc/bind9
pkg:github/isc/bind9
Affected versions
>=9.11.0 <=9.18.50>=9.20.0 <=9.20.27>=9.21.0 <=9.21.25>=9.11.3-S1 <=9.18.50-S1>=9.20.9-S1 <=9.20.27-S1

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AI-Powered Analysis

Machine-generated threat intelligence

AILast updated: 09/16/2026, 14:46:36 UTC

Technical Analysis

The vulnerability arises when a BIND resolver queries a DNSSEC-signed authoritative zone and receives a valid wildcard answer with a signed NSEC3 proof, followed by an unsigned NSEC record at the same owner name. This sequence triggers a reachable assertion failure in the code, causing the program to exit unexpectedly. The affected versions include 9.11.0 through 9.18.50, 9.20.0 through 9.20.27, 9.21.0 through 9.21.25, and their corresponding S1 variants. The CVSS v3.1 base score is 7.5, indicating high severity, with an impact on availability (denial of service) but no confidentiality or integrity impact.

Potential Impact

Successful exploitation causes the BIND resolver to terminate unexpectedly, resulting in denial of service. There is no impact on confidentiality or integrity. No known exploits are reported in the wild at this time.

Mitigation Recommendations

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or patch links are provided in the available data. Users should monitor ISC advisories for updates and consider workarounds or mitigations if available.

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Technical Details

Data Version
5.2
Assigner Short Name
isc
Date Reserved
2026-08-26T07:08:07.730Z
Cvss Version
3.1
State
PUBLISHED

Threat ID: 6aaaa87255bf5e2cf5bb988d

Added to database: 09/16/2026, 14:32:18 UTC

Last enriched: 09/16/2026, 14:46:36 UTC

Last updated: 09/16/2026, 14:46:44 UTC

Views: 5

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