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High ALAS2-2026-3924 1 CVE

Important: python3-tornado security update (Amazon Linux 2)

Published Sep 28, 2026 · Updated Sep 28, 2026

Summary

Package updates are available for Amazon Linux 2 that fix the following vulnerabilities: CVE-2026-82397: Tornado is a Python web framework and asynchronous networking library. Prior to 6.5.8, Tornado parses application/x-www-form-urlencoded request bodies with urllib.parse.parse_qs in tornado/escape.py without passing max_num_fields. RequestHandler._execute in tornado/web.py parses the body before handler dispatch through HTTPServerRequest._parse_body and parse_body_arguments in tornado/httputil.py, so an unauthenticated request body containing millions of separator-delimited fields can synchronously stall the single-threaded event loop and delay every connection. The body is bounded only by max_buffer_size, which defaults to 104857600 bytes. This issue is fixed in version 6.5.8.

Fixed packages 3

ReleasePackageFixed in
Amazon Linux · 2 python3-tornado 0:5.0.2-4.amzn2.0.10
Amazon Linux · 2 python3-tornado-debuginfo 0:5.0.2-4.amzn2.0.10
Amazon Linux · 2 python3-tornado-doc 0:5.0.2-4.amzn2.0.10

Vulnerabilities 1

References

  • web
    https://alas.aws.amazon.com/cve/html/CVE-2026-82397.html