CVE-2026-59928
7.5
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Exploitability: 3.9 / Impact: 3.6
Source: security-advisories@github.com (Secondary)
Description
Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, a Markdown document containing many repeated or distinct reference-link definitions causes quadratic work in src/mistune/block_parser.py and the ref_links environment dictionary handling, allowing denial of service through CPU exhaustion. This issue is fixed in version 3.3.0.
Affected (1)
Products: Mistune Project: Mistune
Configuration A
| Vulnerable Software | Affected Versions |
|---|---|
| Before 3.3.0 |
Related CWEs
CWE-1333
Inefficient Regular Expression Complexity
The product uses a regular expression with an inefficient, possibly exponential worst-case computational complexity that consumes excessive CPU cycles.
CWE-407
Inefficient Algorithmic Complexity
An algorithm in a product has an inefficient worst-case computational complexity that may be detrimental to system performance and can be triggered by an attacker, typically using crafted manipulations that ensure that the worst case is being reached.
References (4)
Source: security-advisories@github.com
Patch
Source: security-advisories@github.com
Release Notes
Source: security-advisories@github.com
ExploitThird Party Advisory
Source: 134c704f-9b21-4f2e-91b3-4a467353bcc0
ExploitThird Party Advisory
Timeline
No history available yet.