Alibaba Cloud Linux 3 : 0113: python3 (ALINUX3-SA-2026:0113)

critical Nessus Plugin ID 315134

Synopsis

The remote Alibaba Cloud Linux host is missing one or more security updates.

Description

The remote Alibaba Cloud Linux 3 host has packages installed that are affected by multiple vulnerabilities as referenced in the ALINUX3-SA-2026:0113 advisory.

Package updates are available for Alibaba Cloud Linux 3 that fix the following vulnerabilities:

CVE-2026-4786:
Mitgation ofCVE-2026-4519 was incomplete. If the URL contained %action the mitigation could be bypassed for certain browser types the webbrowser.open() API could have commands injected into the underlying shell. SeeCVE-2026-4519 for details.

CVE-2026-6100:
Use-after-free (UAF) was possible in the `lzma.LZMADecompressor`, `bz2.BZ2Decompressor`, and `gzip.GzipFile` when a memory allocation fails with a `MemoryError` and the decompression instance is re- used. This scenario can be triggered if the process is under memory pressure. The fix cleans up the dangling pointer in this specific error condition.
The vulnerability is only present if the program re-uses decompressor instances across multiple decompression calls even after a `MemoryError` is raised during decompression. Using the helper functions to one-shot decompress data such as `lzma.decompress()`, `bz2.decompress()`, `gzip.decompress()`, and `zlib.decompress()` are not affected as a new decompressor instance is used per call. If the decompressor instance is not re-used after an error condition, this usage is similarly not vulnerable.

Tenable has extracted the preceding description block directly from the Alibaba Cloud Linux 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

Update the affected packages.

Plugin Details

Severity: Critical

ID: 315134

File Name: alinux3_sa_2026-0113.nasl

Version: 1.1

Type: Local

Family: Alibaba Cloud Linux Local Security Checks

Published: 5/18/2026

Updated: 5/18/2026

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 6.7

CVSS v2

Risk Factor: High

Base Score: 7.6

Temporal Score: 5.6

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

CVSS Score Source: CVE-2026-6100

CVSS v3

Risk Factor: High

Base Score: 8.1

Temporal Score: 7.1

Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

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

CVSS v4

Risk Factor: Critical

Base Score: 9.1

Threat Score: 6.9

Threat Vector: CVSS:4.0/E:U

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

Vulnerability Information

CPE: cpe:/o:alibabacloud:alibaba_cloud_linux_3, p-cpe:/a:alibabacloud:alibaba_cloud_linux_3:python3-idle, p-cpe:/a:alibabacloud:alibaba_cloud_linux_3:python3-devel, p-cpe:/a:alibabacloud:alibaba_cloud_linux_3:platform-python-debug, p-cpe:/a:alibabacloud:alibaba_cloud_linux_3:platform-python-devel, p-cpe:/a:alibabacloud:alibaba_cloud_linux_3:python3-tkinter, p-cpe:/a:alibabacloud:alibaba_cloud_linux_3:python3-libs, p-cpe:/a:alibabacloud:alibaba_cloud_linux_3:platform-python, p-cpe:/a:alibabacloud:alibaba_cloud_linux_3:python3-test

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

Exploit Ease: No known exploits are available

Patch Publication Date: 5/13/2026

Vulnerability Publication Date: 2/12/2026

Reference Information

CVE: CVE-2026-4786, CVE-2026-6100

Detections

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