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Medium ALAS2023-2026-1367 2 CVEs

Moderate: python3.12-pip security update (Amazon Linux 2023)

Published Jan 23, 2026 · Updated Jan 23, 2026

Summary

Package updates are available for Amazon Linux 2023 that fix the following vulnerabilities: CVE-2025-66471: 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-2025-66418: 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.

Fixed packages 2

ReleasePackageFixed in
Amazon Linux · 2023 python3.12-pip 0:23.2.1-4.amzn2023.0.6
Amazon Linux · 2023 python3.12-pip-wheel 0:23.2.1-4.amzn2023.0.6

Vulnerabilities 2

References

  • web
    https://alas.aws.amazon.com/cve/html/CVE-2025-66418.html
  • web
    https://alas.aws.amazon.com/cve/html/CVE-2025-66471.html