Amazon Linux 2 : bind, --advisory ALAS2-2026-3854 (ALAS-2026-3854)

high Nessus Plugin ID 332027

Synopsis

The remote Amazon Linux 2 host is missing a security update.

Description

The version of bind installed on the remote host is prior to 9.11.4-26.P2. It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2-2026-3854 advisory.

BIND may accept incorrect child-zone NSEC3 records as valid, which could allow an attacker to forge authenticated NXDOMAIN responses.This issue affects BIND 9 versions 9.18.0 through 9.18.50, 9.20.0 through 9.20.24, 9.21.0 through 9.21.23, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.24-S1.
(CVE-2026-10723)

A DNSSEC validating resolver that is under a random subdomain attack against a DNSSEC-signed zone can suffer from runaway memory usage. The attacker needs to be able to send queries faster than the resolver can perform validation. The increased memory usage can be orders of magnitude beyond the limit configured in the `max-cache-size` parameter.This issue 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, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.24-S1.
(CVE-2026-11622)

It is possible for an attacker's zone to respond to a query with an RRSIG that has a smaller number of labels than the zone in which the RRSIG is contained. This causes `named` to produce a wildcard name for a zone that is shorter than the attacker's zone, which can result in cache poisoning. For this attack to have any effect, the resolver under attack must have set `synth-from-dnssec yes;` (which is the default).This issue 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, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.24-S1. (CVE-2026-11721)

If a provably insecure domain is covered by both an NSEC and NSEC3 record at the parent, and there exist an RRSIG for only one of these types, then BIND may exit unexpectedly with an assertion while validating this proof.This issue 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, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.24-S1. (CVE-2026-13204)

The BIND resolver accepts validly-signed NSEC records where the Next Domain Name field points outside the signer's zone.This issue 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, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.24-S1. (CVE-2026-13321)

Tenable has extracted the preceding description block directly from the tested product security advisory.

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

Solution

Run 'yum update bind' or or 'yum update --advisory ALAS2-2026-3854' to update your system.

See Also

https://alas.aws.amazon.com//AL2/ALAS2-2026-3854.html

https://alas.aws.amazon.com/faqs.html

https://explore.alas.aws.amazon.com/CVE-2026-10723.html

https://explore.alas.aws.amazon.com/CVE-2026-11622.html

https://explore.alas.aws.amazon.com/CVE-2026-11721.html

https://explore.alas.aws.amazon.com/CVE-2026-13204.html

https://explore.alas.aws.amazon.com/CVE-2026-13321.html

Plugin Details

Severity: High

ID: 332027

File Name: al2_ALAS-2026-3854.nasl

Version: 1.1

Type: Local

Agent: unix

Published: 8/4/2026

Updated: 8/4/2026

Supported Sensors: Agentless Assessment, Continuous Assessment, Frictionless Assessment Agent, Frictionless Assessment AWS, Nessus Agent, Tenable Cloud Security, Tenable Self-Hosted Container Security, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 5

Percentile: 93.92

CVSS v2

Risk Factor: High

Base Score: 7.8

Temporal Score: 5.8

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

CVSS Score Source: CVE-2026-13321

CVSS v3

Risk Factor: High

Base Score: 8.6

Temporal Score: 7.5

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

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:amazon:linux:2, p-cpe:/a:amazon:linux:bind-chroot, p-cpe:/a:amazon:linux:bind-debuginfo, p-cpe:/a:amazon:linux:bind-devel, p-cpe:/a:amazon:linux:bind-export-devel, p-cpe:/a:amazon:linux:bind-export-libs, p-cpe:/a:amazon:linux:bind-libs-lite, p-cpe:/a:amazon:linux:bind-libs, p-cpe:/a:amazon:linux:bind-license, p-cpe:/a:amazon:linux:bind-lite-devel, p-cpe:/a:amazon:linux:bind-pkcs11-devel, p-cpe:/a:amazon:linux:bind-pkcs11-libs, p-cpe:/a:amazon:linux:bind-pkcs11-utils, p-cpe:/a:amazon:linux:bind-pkcs11, p-cpe:/a:amazon:linux:bind-sdb-chroot, p-cpe:/a:amazon:linux:bind-sdb, p-cpe:/a:amazon:linux:bind-utils, p-cpe:/a:amazon:linux:bind

Required KB Items: Host/local_checks_enabled, Host/AmazonLinux/release, Host/AmazonLinux/rpm-list

Exploit Ease: No known exploits are available

Patch Publication Date: 8/4/2026

Vulnerability Publication Date: 7/22/2026

Reference Information

CVE: CVE-2026-10723, CVE-2026-11622, CVE-2026-11721, CVE-2026-13204, CVE-2026-13321

IAVA: 2026-A-0764