Unity Linux 20.1070a Security Update: python3.11 (UTSA-2026-150503)

critical Nessus Plugin ID 376559

Synopsis

The Unity Linux host is missing one or more security updates.

Description

The Unity Linux 20 host has a package installed that is affected by a vulnerability as referenced in the UTSA-2026-150503 advisory.

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 Unity Linux 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

Update the affected python3.11 package.

See Also

https://access.redhat.com/security/cve/CVE-2026-6100

https://github.com/python/cpython/issues/148395

https://github.com/python/cpython/pull/148396

http://www.nessus.org/u?1c0f6599

http://www.nessus.org/u?51457640

http://www.nessus.org/u?5a578f3b

http://www.nessus.org/u?5fb8a6df

http://www.nessus.org/u?704644c1

http://www.nessus.org/u?8d9428f8

http://www.nessus.org/u?9ed989e5

http://www.nessus.org/u?c5946b4b

Plugin Details

Severity: Critical

ID: 376559

File Name: unity_linux_UTSA-2026-150503.nasl

Version: 1.1

Type: Local

Published: 11/5/2026

Updated: 11/5/2026

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 6.9

Percentile: 96.5

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

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

Exploit Ease: No known exploits are available

Patch Publication Date: 11/5/2026

Vulnerability Publication Date: 2/12/2026

Reference Information

CVE: CVE-2026-6100