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© 2026 FAUCET Technologies LLC. All rights reserved.

CVE-2026-59923

29
FAUCET Score

Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, HTMLRenderer.safe_url() does not block percent-encoded javascript URIs, allowing attacker-supplied Markdown links or images to bypass URL protections and execute script in rendered HTML. This issue is fixed in version 3.3.0.

First published: Jul 8, 2026Last modified: Jul 8, 2026

Impacted Technologies

VendorProductVersion(s)CPE
< 3.3.0CPE matchmatch criteria
cpe:2.3:a:mistune_project:mistune:*:*:*:*:*:*:*:*

CVSS Data

CVSS version used by this source: 3.1

6.1MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
REQUIRED
Scope
CHANGED
Confidentiality Impact
LOW
Integrity Impact
LOW
Availability Impact
NONE
Exploitability Score
2.8
Impact Score
2.7
CvssVersion
3.1

Exploit Intelligence

EPSS Score
0.24%
Probability of exploitation in next 30 days
EPSS Percentile
15.0%
Percentile rank of EPSS score among Peer Group
As of 2026-07-27
Model: v2026.06.15
This CVE's current EPSS score of 0.0024 is in the 16th percentile among its peer group of 26,221 CVEs.

Social Chatter

The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.1 Bluesky, 0.0 Mastodon, and 0.1 GitHub mentions.

Media Mentions

No media coverage found for this CVE.

The average CVE in this peer group has 0.1 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.

Remediation

Patch Available

Vendor Patches (2)

github_advisorypatch availablevia nvd_reference
View patch
pippatch availablevia ghsa
Product: mistuneFixed in: 3.3.0

Vendor Advisories (1)

pipGHSA-8c25-4j27-2rv3medium

Mistune: XSS via percent-encoded javascript URI bypass in safe_url()

Jul 20, 2026

References

github.com / lepture/mistune/commit/c7101fcbb6e8790e8e39157c5ca2238fc6dd6cbc
Patch
github.com / lepture/mistune/releases/tag/v3.3.0
Release Notes
github.com / lepture/mistune/security/advisories/GHSA-8c25-4j27-2rv3
ExploitVendor Advisory