Amazon Linux 2 : squid (ALAS-2026-3961)

high Nessus Plugin ID 351081

Synopsis

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

Description

The version of squid installed on the remote host is prior to 3.5.20-17. It is, therefore, affected by a vulnerability as referenced in the ALAS2-2026-3961 advisory.

Due to a CWE-841 Improper Enforcement of Behavioral Workflowbug Squid is vulnerable to a Request Smuggling attack againstHTTP/1.1 Transfer-Encoding.

This problem allows a trusted client to perform an HTTP RequestSmuggling attack when HTTP/1.1 is used.
Bypassing securitymechanisms that may be in place between attacker and Squid.

When there is an HTTP cache operating prior to the affectedSquid, this Request Smuggling attack also allows the attackerto poison that web cache and store arbitrary malicious contentat any URL for delivery to other clients future requests. (CVE-2026-61642)

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 squid' or or 'yum update --advisory ALAS2-2026-3961' to update your system.

Plugin Details

Severity: High

ID: 351081

File Name: al2_ALAS-2026-3961.nasl

Version: 1.1

Type: Local

Agent: unix

Family: Amazon Linux Local Security Checks

Published: 9/29/2026

Updated: 9/29/2026

Supported Sensors: Nessus Agent, Continuous Assessment, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 5

Percentile: 93.22

CVSS v2

Risk Factor: Medium

Base Score: 6.4

Temporal Score: 4.7

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

CVSS Score Source: CVE-2026-61642

CVSS v3

Risk Factor: High

Base Score: 7.5

Temporal Score: 6.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/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:squid-debuginfo, p-cpe:/a:amazon:linux:squid-migration-script, p-cpe:/a:amazon:linux:squid-sysvinit, p-cpe:/a:amazon:linux:squid

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

Exploit Ease: No known exploits are available

Patch Publication Date: 9/28/2026

Vulnerability Publication Date: 9/28/2026

Reference Information

CVE: CVE-2026-61642

Detections

Analytics