Detections
Analytics
Amazon Linux 2 : python-virtualenv (ALAS-2026-4085)
high Nessus Plugin ID 377963
Synopsis
The remote Amazon Linux 2 host is missing a security update.Description
The version of python-virtualenv installed on the remote host is prior to 15.1.0-4. It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2-2026-4085 advisory.virtualenv is a tool for creating isolated virtual python environments. Prior to 21.14.9, caller-supplied prompt text can become executable syntax in the bash activation prompt. An attacker must influence the value passed to virtualenv, and a user must subsequently activate the environment and draw the prompt.
This vulnerability is fixed in 21.14.9. (CVE-2026-113723)
virtualenv is a tool for creating isolated virtual python environments. Prior to 21.14.7, the bash activate script escapes the environment name for only one of the two passes bash makes over PS1, so a backslash in the name undoes the escaping and a name containing \$(...) runs as commands in the user's shell each time bash draws the prompt. This issue is fixed in version 21.14.7. (CVE-2026-113725)
virtualenv is a tool for creating isolated virtual python environments. Prior to 21.13.0, the bash activate script that zsh also sources leaves the environment name unescaped; from 21.13.0 until 21.14.4, it escapes backslashes, dollar signs, and backticks only when BASH_VERSION is set, so zsh receives the raw value. The script assigns that value to PS1. In zsh with PROMPT_SUBST, an attacker-influenced environment directory, --prompt, or VIRTUALENV_PROMPT value containing command, parameter, or arithmetic expansion syntax can therefore execute commands in the user's shell each time the prompt is drawn. A percent sign is separately interpreted as a zsh prompt escape but does not by itself execute commands. Plain zsh with PROMPT_SUBST disabled and bash are not affected by this mechanism. This issue is fixed in version 21.14.4.
(CVE-2026-113726)
virtualenv is a tool for creating isolated virtual python environments. From 21.14.9 until 21.14.13, the bash bin/activate script can copy an attacker-controlled --prompt value into PS1 without escaping dollar signs or backticks when both promptvars and POSIX mode are disabled during activation. Re-enabling promptvars, running set -o posix, or starting an interactive child bash that inherits the exported PS1 can then expand command substitution in the stored VIRTUAL_ENV_PROMPT value and execute commands as the user who activates the environment. This issue is fixed in version 21.14.13. (CVE-2026-115586)
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 python-virtualenv' or or 'yum update --advisory ALAS2-2026-4085' to update your system.See Also
https://alas.aws.amazon.com//AL2/ALAS2-2026-4085.html
https://alas.aws.amazon.com/faqs.html
https://explore.alas.aws.amazon.com/CVE-2026-113723.html
https://explore.alas.aws.amazon.com/CVE-2026-113725.html
Plugin Details
Severity: High
ID: 377963
File Name: al2_ALAS-2026-4085.nasl
Version: 1.1
Type: Local
Agent: unix
Published: 11/9/2026
Updated: 11/9/2026
Supported Sensors: Nessus Agent, Continuous Assessment, Nessus
Risk Information
VPR
Risk Factor: Medium
Score: 5
Percentile: 92.81
CVSS v2
Risk Factor: High
Base Score: 7.2
Temporal Score: 5.3
Vector: CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C
CVSS Score Source: CVE-2026-113726
CVSS v3
Risk Factor: High
Base Score: 7.8
Temporal Score: 6.8
Vector: CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C
CVSS v4
Risk Factor: High
Base Score: 7.1
Threat Score: 4
Threat Vector: CVSS:4.0/E:U
Vector: CVSS:4.0/AV:L/AC:H/AT:P/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
CVSS Score Source: CVE-2026-115586
Vulnerability Information
CPE: cpe:/o:amazon:linux:2, p-cpe:/a:amazon:linux:python-virtualenv
Required KB Items: Host/local_checks_enabled, Host/AmazonLinux/release, Host/AmazonLinux/rpm-list
Exploit Ease: No known exploits are available
Patch Publication Date: 11/9/2026
Vulnerability Publication Date: 10/20/2026
Reference Information
CVE: CVE-2026-113723, CVE-2026-113725, CVE-2026-113726, CVE-2026-115586