Amazon Linux 2023 : cifs-utils, cifs-utils-devel, cifs-utils-info (ALAS2023-2026-2030)

high Nessus Plugin ID 332001

Synopsis

The remote Amazon Linux 2023 host is missing a security update.

Description

It is, therefore, affected by a vulnerability as referenced in the ALAS2023-2026-2030 advisory.

A flaw was found in the cifs-utils package where the cifs.upcall helper fails to securely drop its root privileges before looking up user information inside a user-controlled environment. A local, low privileged attacker can exploit this by using a crafted request_key payload to trick the root-owned helper into entering a custom environment (namespace) containing a malicious NSS module. This forces the system to load the attacker's controlled NSS Module and configuration, allowing them to execute arbitrary commands as the root user, elevating their privileges and fully compromising the system. (CVE-2026-12505)

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 'dnf update cifs-utils --releasever 2023.12.20260803' or or 'dnf update --advisory ALAS2023-2026-2030 --releasever 2023.12.20260803' to update your system.

Plugin Details

Severity: High

ID: 332001

File Name: al2023_ALAS2023-2026-2030.nasl

Version: 1.1

Type: Local

Agent: unix

Family: Amazon Linux Local Security Checks

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: 4.9

Percentile: 58.04

CVSS v2

Risk Factor: Medium

Base Score: 6.8

Temporal Score: 5

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

CVSS Score Source: CVE-2026-12505

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 6.8

Vector: CVSS:3.0/AV:L/AC:L/PR:L/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:2023, p-cpe:/a:amazon:linux:cifs-utils-debuginfo, p-cpe:/a:amazon:linux:cifs-utils-debugsource, p-cpe:/a:amazon:linux:cifs-utils-devel, p-cpe:/a:amazon:linux:cifs-utils-info, p-cpe:/a:amazon:linux:cifs-utils, p-cpe:/a:amazon:linux:pam_cifscreds-debuginfo, p-cpe:/a:amazon:linux:pam_cifscreds

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: 6/9/2026

Reference Information

CVE: CVE-2026-12505

IAVB: 2026-B-0164

Detections

Analytics