Amazon Linux 2 : perl-CGI-Session, --advisory ALAS2-2026-3805 (ALAS-2026-3805)

medium Nessus Plugin ID 328847

Synopsis

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

Description

The version of perl-CGI-Session installed on the remote host is prior to 4.35-16. It is, therefore, affected by a vulnerability as referenced in the ALAS2-2026-3805 advisory.

CGI::Session::ID::md5 versions before 4.49 for Perl generate predictable session ids from low-entropy sources.

The generate_id method builds the session id from a MD5 digest of the process id, the epoch time, and the built-in rand() function. All three are predictable, low-entropy sources: the PID is drawn from a small range, the epoch time can be guessed or read from the HTTP Date header, and Perl's rand() is unsuitable for security purposes because it is predictable and reversible.

An attacker who predicts a session id can impersonate the corresponding session and bypass authentication.
(CVE-2026-56016)

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 perl-CGI-Session' or or 'yum update --advisory ALAS2-2026-3805' to update your system.

Plugin Details

Severity: Medium

ID: 328847

File Name: al2_ALAS-2026-3805.nasl

Version: 1.1

Type: Local

Agent: unix

Family: Amazon Linux Local Security Checks

Published: 7/21/2026

Updated: 7/21/2026

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

Risk Information

VPR

Risk Factor: Low

Score: 3

Percentile: 23.75

CVSS v2

Risk Factor: Medium

Base Score: 5.4

Temporal Score: 4

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

CVSS Score Source: CVE-2026-56016

CVSS v3

Risk Factor: Medium

Base Score: 5.9

Temporal Score: 5.2

Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/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:perl-cgi-session

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

Exploit Ease: No known exploits are available

Patch Publication Date: 7/20/2026

Vulnerability Publication Date: 7/1/2026

Reference Information

CVE: CVE-2026-56016

Detections

Analytics