6.1

CVE-2026-44708: Mistune Math Plugin XSS Escape Bypass

Analyzed
AliasesGHSA-8g87-j6q8-g93xPYSEC-2026-2206UBUNTU-CVE-2026-44708
Published 26-05-2026Last modified 27-05-2026

Vulnerability summary

CVE-2026-44708 is a medium (CVSS 6.1) vulnerability in lepture mistune. EPSS estimates a 0.23% chance of exploitation in the next 30 days, higher than 13.6% of scored vulnerabilities. 1 public exploit is recorded.

Priority
Routine

Not severe (CVSS 6.1, network access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
6.1/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.23%
0%100%
Low · -0.04 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits1github

Advisory lineage

Upstream 0 · Downstream 0 · Related 1
CGA-23JX-75X6-QPHX

Timeline

  1. 26-05-2026
    PublishedVulnerability first disclosed.
  2. 27-05-2026
    Last modifiedVulnerability information updated.

Description

Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.2.1, the mistune math plugin renders inline math ($...$) and block math ($$...$$) by concatenating the raw user-supplied content directly into the HTML output without any HTML escaping. This occurs even when the parser is explicitly created with escape=True, which is supposed to guarantee that all user-controlled text is sanitised before reaching the DOM. This vulnerability is fixed in 3.2.1.

CVSS metrics

7 scores · 7 sources · 1 version

EPSS trend

Probability

0.23%

Chance of exploitation in the next 30 days

Percentile

14%

Versus all other CVEs

30-day change

Decrease -0.04 pp

From 0.27% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

1 found
  • githubUnverified

    Mistune

    Maturity: poc

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: network-reachable, no authentication, user interaction (CVSS vector). Other conditions: not stated in public data.

Chainguard2 products
  • datahub-ingestion-fips< 1.5.0.1-r2
  • kubeflow-pipelines-visualization-server< 2.16.1-r2
Ubuntu2 products
  • mistuneAll versions (No fix recorded)
  • mistune0All versions (No fix recorded)
Debian1 product
  • mistuneAll versions (No fix recorded)
Lepture1 product
Mistune_project1 product
PyPI1 product
  • mistune≤ 3.2.0 | < 3.2.1
Wolfi1 product
  • kubeflow-pipelines-visualization-server< 2.16.1-r2

7 vendors · 9 products

References

8 links