RHEL 7 : python-s3transfer (RHSA-2026:1337)

high Nessus Plugin ID 296763

Synopsis

The remote Red Hat host is missing a security update for python-s3transfer.

Description

The remote Redhat Enterprise Linux 7 host has a package installed that is affected by a vulnerability as referenced in the RHSA-2026:1337 advisory.

Python is an interpreted, interactive, object-oriented programming language, which includes modules, classes, exceptions, very high level dynamic data types and dynamic typing. Python supports interfaces to many system calls and libraries, as well as to various windowing systems.

Security Fix(es):

* urllib3: urllib3: Unbounded decompression chain leads to resource exhaustion (CVE-2025-66418)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Tenable has extracted the preceding description block directly from the Red Hat Enterprise 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 RHEL python-s3transfer package based on the guidance in RHSA-2026:1337.

See Also

https://access.redhat.com/security/updates/classification/#important

https://bugzilla.redhat.com/show_bug.cgi?id=2419455

http://www.nessus.org/u?31700d2c

https://access.redhat.com/errata/RHSA-2026:1337

Plugin Details

Severity: High

ID: 296763

File Name: redhat-RHSA-2026-1337.nasl

Version: 1.1

Type: local

Agent: unix

Published: 1/27/2026

Updated: 1/27/2026

Supported Sensors: Agentless Assessment, Continuous Assessment, Frictionless Assessment Agent, Frictionless Assessment AWS, Frictionless Assessment Azure, Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: Low

Score: 3.6

Vendor

Vendor Severity: Important

CVSS v2

Risk Factor: High

Base Score: 7.8

Temporal Score: 5.8

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

CVSS Score Source: CVE-2025-66418

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: High

Base Score: 8.9

Threat Score: 6.3

Threat Vector: CVSS:4.0/E:U

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

Vulnerability Information

CPE: p-cpe:/a:redhat:enterprise_linux:python-s3transfer, cpe:/o:redhat:enterprise_linux:7

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

Exploit Ease: No known exploits are available

Patch Publication Date: 1/27/2026

Vulnerability Publication Date: 12/5/2025

Reference Information

CVE: CVE-2025-66418

CWE: 770

RHSA: 2026:1337