Detections
Analytics
Amazon Linux 2 : python-urllib3, --advisory ALAS2-2025-3110 (ALAS-2025-3110)
high Nessus Plugin ID 281822
Language:
Synopsis
The remote Amazon Linux 2 host is missing a security update.Description
The version of python-urllib3 installed on the remote host is prior to 1.25.9-1. It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2-2025-3110 advisory.urllib3 is a user-friendly HTTP client library for Python. Starting in version 1.24 and prior to 2.6.0, the number of links in the decompression chain was unbounded allowing a malicious server to insert a virtually unlimited number of compression steps leading to high CPU usage and massive memory allocation for the decompressed data. This vulnerability is fixed in 2.6.0. (CVE-2025-66418)
urllib3 is a user-friendly HTTP client library for Python. Starting in version 1.0 and prior to 2.6.0, the Streaming API improperly handles highly compressed data. urllib3's streaming API is designed for the efficient handling of large HTTP responses by reading the content in chunks, rather than loading the entire response body into memory at once. When streaming a compressed response, urllib3 can perform decoding or decompression based on the HTTP Content-Encoding header (e.g., gzip, deflate, br, or zstd).
The library must read compressed data from the network and decompress it until the requested chunk size is met. Any resulting decompressed data that exceeds the requested amount is held in an internal buffer for the next read operation. The decompression logic could cause urllib3 to fully decode a small amount of highly compressed data in a single operation. This can result in excessive resource consumption (high CPU usage and massive memory allocation for the decompressed data. (CVE-2025-66471)
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-urllib3' or or 'yum update --advisory ALAS2-2025-3110' to update your system.See Also
https://alas.aws.amazon.com//AL2/ALAS2-2025-3110.html
https://alas.aws.amazon.com/faqs.html
Plugin Details
Severity: High
ID: 281822
File Name: al2_ALAS-2025-3110.nasl
Version: 1.1
Type: local
Agent: unix
Published: 1/5/2026
Updated: 1/5/2026
Supported Sensors: Frictionless Assessment AWS, Frictionless Assessment Agent, Nessus Agent, Agentless Assessment, Continuous Assessment, Nessus
Risk Information
VPR
Risk Factor: Medium
Score: 4.4
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-2025-66471
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: cpe:/o:amazon:linux:2, p-cpe:/a:amazon:linux:python-urllib3
Required KB Items: Host/local_checks_enabled, Host/AmazonLinux/release, Host/AmazonLinux/rpm-list
Exploit Ease: No known exploits are available
Patch Publication Date: 1/5/2026
Vulnerability Publication Date: 12/5/2025
Reference Information
CVE: CVE-2025-66418, CVE-2025-66471