Amazon Linux 2023 : python3.11, python3.11-devel, python3.11-idle (ALAS2023-2026-2125)

low Nessus Plugin ID 341864

Synopsis

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

Description

It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2023-2026-2125 advisory.

Attacker-controlled CSV samples can trigger super-linear regular-expression work during dialect sniffing and consume significant CPU when applications pass unbounded input to csv.Sniffer.sniff().
(CVE-2026-18503)

`Element.findall()` and fully-consumed `Element.iterfind()` exhibit `O(n^2)` time complexity when using XPath index predicates (e.g. `[1]`, `[last()]`, `[last()-N]`) on XML documents with many same-tag siblings. `Element.find()` is only affected when the first match is near the end of the sibling list, such as with `[last()]` or `[last()-N]`; `.//item[1]` short-circuits after the first match.
(CVE-2026-6879)

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 'dnf update python3.11 --releasever 2023.12.20260831' or or 'dnf update --advisory ALAS2023-2026-2125 --releasever 2023.12.20260831' to update your system.

See Also

https://alas.aws.amazon.com//AL2023/ALAS2023-2026-2125.html

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

https://explore.alas.aws.amazon.com/CVE-2026-18503.html

https://explore.alas.aws.amazon.com/CVE-2026-6879.html

Plugin Details

Severity: Low

ID: 341864

File Name: al2023_ALAS2023-2026-2125.nasl

Version: 1.1

Type: Local

Agent: unix

Published: 8/31/2026

Updated: 8/31/2026

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: Low

Score: 3

Percentile: 23.61

CVSS v2

Risk Factor: Medium

Base Score: 5

Temporal Score: 3.7

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

CVSS Score Source: CVE-2026-6879

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:N/A:H

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

CVSS v4

Risk Factor: Low

Base Score: 2.4

Threat Score: 0.4

Threat Vector: CVSS:4.0/E:U

Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N

CVSS Score Source: CVE-2026-18503

Vulnerability Information

CPE: cpe:/o:amazon:linux:2023, p-cpe:/a:amazon:linux:python3.11-debug, p-cpe:/a:amazon:linux:python3.11-debuginfo, p-cpe:/a:amazon:linux:python3.11-debugsource, p-cpe:/a:amazon:linux:python3.11-devel, p-cpe:/a:amazon:linux:python3.11-idle, p-cpe:/a:amazon:linux:python3.11-libs, p-cpe:/a:amazon:linux:python3.11-test, p-cpe:/a:amazon:linux:python3.11-tkinter, p-cpe:/a:amazon:linux:python3.11

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

Exploit Ease: No known exploits are available

Patch Publication Date: 8/31/2026

Vulnerability Publication Date: 6/11/2026

Reference Information

CVE: CVE-2026-18503, CVE-2026-6879

IAVA: 2026-A-0549-S