Amazon Linux 2 : 389-ds-base (ALAS-2026-3909)

critical Nessus Plugin ID 344423

Synopsis

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

Description

The version of 389-ds-base installed on the remote host is prior to 1.3.10.2-17. It is, therefore, affected by a vulnerability as referenced in the ALAS2-2026-3909 advisory.

A flaw was found in 389 Directory Server. During SASL PLAIN authentication, a stale identity carried in a Cyrus SASL auxiliary property from a prior failed bind attempt can be installed on a connection following a subsequent, unrelated successful bind, regardless of which SASL mechanism completes that second bind. An attacker can send a SASL PLAIN bind as cn=Directory Manager with an incorrect password, then complete a SASL ANONYMOUS bind on the same connection, causing the server to grant Directory Manager authority without any valid credentials. A variant using a valid low-privileged account's own successful bind instead of an anonymous one is also possible. (CVE-2026-18922)

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

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

Solution

Run 'yum update 389-ds-base' or or 'yum update --advisory ALAS2-2026-3909' to update your system.

See Also

https://alas.aws.amazon.com//AL2/ALAS2-2026-3909.html

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

https://explore.alas.aws.amazon.com/CVE-2026-18922.html

Plugin Details

Severity: Critical

ID: 344423

File Name: al2_ALAS-2026-3909.nasl

Version: 1.1

Type: Local

Agent: unix

Published: 9/9/2026

Updated: 9/9/2026

Supported Sensors: Nessus Agent, Continuous Assessment, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 6.9

Percentile: 96.6

CVSS v2

Risk Factor: Critical

Base Score: 10

Temporal Score: 7.4

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

CVSS Score Source: CVE-2026-18922

CVSS v3

Risk Factor: Critical

Base Score: 9.8

Temporal Score: 8.5

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

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

Vulnerability Information

CPE: cpe:/o:amazon:linux:2, p-cpe:/a:amazon:linux:389-ds-base-debuginfo, p-cpe:/a:amazon:linux:389-ds-base-devel, p-cpe:/a:amazon:linux:389-ds-base-libs, p-cpe:/a:amazon:linux:389-ds-base-snmp, p-cpe:/a:amazon:linux:389-ds-base

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

Exploit Ease: No known exploits are available

Patch Publication Date: 9/8/2026

Vulnerability Publication Date: 9/7/2026

Reference Information

CVE: CVE-2026-18922