CVE-2026-59926

MEDIUM
MEDIUM Priority: 0.02 BB Relevance: 61/100
Published: 2026-07-08 Modified: 2026-10-25 First seen: 2026-10-29 Status: active

Attack Surface

Network Low Complexity No Auth

CVSS Vector Breakdown

AV: Network
AC: Low
PR: None
UI: Passive
S: X
AT: None
VC: Low
VI: Low
VA: None

Description

Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.2.1, render_admonition() in src/mistune/directives/admonition.py concatenates the Admonition directive :class: option into the HTML class attribute without escaping, allowing attribute injection and cross-site scripting even when HTMLRenderer escape mode is enabled. This issue is fixed in version 3.2.1.

Weakness Classification (1)

Affected Software (1)

VendorProductVersion
mistune_project mistune < 3.3.0

Bug Bounty Relevance

61 / 100
✓ Network accessible
✓ No authentication
✓ Low complexity

CVSS Score

5.3 / 10.0 v4.0
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

EPSS — Exploitation Probability

0.33%
Raw Score 0.003270
Percentile 25.7%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00327
2026-10-28
0.00327

Intelligence Sources

nvd ref →