ISC BIND 9.11.0 < 9.20.29 / 9.11.3-S1 < 9.20.29-S1 / 9.20.0 < 9.20.29 / 9.20.9-S1 < 9.20.29-S1 / 9.21.0 < 9.21.26 Multiple Vulnerabilities

high Nessus Plugin ID 347969

Synopsis

The remote name server is affected by multiple vulnerabilities.

Description

The version of ISC BIND running on the remote host is 9.11.0 through 9.18.50, 9.20.0 through 9.20.27, or 9.21.0 through 9.21.25. Supported Preview Edition releases 9.11.3-S1 through 9.18.50-S1 and 9.20.9-S1 through 9.20.27-S1 are also affected. It is, therefore, affected by multiple vulnerabilities :

- 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. (CVE-2026-80274)

- A validly signed NSEC3 from an unrelated sibling zone may be accepted as an insecurity proof, downgrading a secure delegation and letting a forged unsigned answer through. (CVE-2026-77119)

- A malformed zone may contain an NS or DNAME node above its origin, which named treats as a zone cut. If an attacker inserts a malformed zone into a BIND authoritative server (e.g., via zone transfer), queries for names inside the configured zone then lose authoritative status and return an out-of-zone delegation.
(CVE-2026-78301)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Upgrade to ISC BIND version 9.20.29 / 9.20.29-S1 / 9.21.26 or later. Note that the 9.18 branch is end of life and no fix is available for it; migrate to a supported branch.

Plugin Details

Severity: High

ID: 347969

File Name: bind9_92126_cve-2026-80274.nasl

Version: 1.2

Type: Remote

Family: DNS

Published: 9/18/2026

Updated: 9/18/2026

Configuration: Enable paranoid mode

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 5.3

Percentile: 95.88

CVSS v2

Risk Factor: High

Base Score: 7.8

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C

CVSS Score Source: CVE-2026-80274

CVSS v3

Risk Factor: High

Base Score: 7.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Vulnerability Information

CPE: cpe:/a:isc:bind

Required KB Items: Settings/ParanoidReport, bind/version

Patch Publication Date: 9/16/2026

Vulnerability Publication Date: 9/16/2026

Reference Information

CVE: CVE-2026-77119, CVE-2026-78301, CVE-2026-80274

IAVA: 2026-A-1029

Detections

Analytics