Resource Exhaustion Affecting python-tornado package, versions <6.0.3+really5.1.1-3ubuntu0.1~esm5


Severity

Recommended
medium

Based on Ubuntu security rating.

Threat Intelligence

EPSS
0.51% (42nd percentile)

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  • Snyk IDSNYK-UBUNTU2004-PYTHONTORNADO-15517667
  • published23 Apr 2026
  • disclosed11 Mar 2026

Introduced: 11 Mar 2026

CVE-2026-31958  (opens in a new tab)
CWE-400  (opens in a new tab)

How to fix?

Upgrade Ubuntu:20.04 python-tornado to version 6.0.3+really5.1.1-3ubuntu0.1~esm5 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream python-tornado package and not the python-tornado package as distributed by Ubuntu. See How to fix? for Ubuntu:20.04 relevant fixed versions and status.

Tornado is a Python web framework and asynchronous networking library. In versions of Tornado prior to 6.5.5, the only limit on the number of parts in multipart/form-data is the max_body_size setting (default 100MB). Since parsing occurs synchronously on the main thread, this creates the possibility of denial-of-service due to the cost of parsing very large multipart bodies with many parts. This vulnerability is fixed in 6.5.5.

CVSS Base Scores

version 3.1