Inefficient Algorithmic Complexity Affecting mistune package, versions [,3.3.0)


Severity

Recommended
0.0
high
0
10

CVSS assessment by Snyk's Security Team. Learn more

Threat Intelligence

EPSS
0.41% (34th percentile)

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  • Snyk IDSNYK-PYTHON-MISTUNE-17895071
  • published8 Jul 2026
  • disclosed8 Jul 2026
  • creditoffset

Introduced: 8 Jul 2026

CVE-2026-59925  (opens in a new tab)
CWE-407  (opens in a new tab)

How to fix?

Upgrade mistune to version 3.3.0 or higher.

Overview

Affected versions of this package are vulnerable to Inefficient Algorithmic Complexity in the inline_parser process. An attacker can cause excessive resource consumption by submitting input containing long sequences of double-asterisk or triple-asterisk emphasis pairs, leading to significant performance degradation.

CVSS Base Scores

version 4.0
version 3.1