Medium severity · published Jul 8, 2026
CVE-2026-59924
Mistune: Arbitrary File Read via Include directive path traversal
5.9
CVSS
0.5%
EPSS
No
On KEV
Description
Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, Include.parse() joins and normalizes user-supplied include paths without verifying that the result remains within the intended markdown directory, allowing crafted include paths to access files outside that directory when markdown files are processed using md.read(). This issue is fixed in version 3.3.0.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 40% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MI
mistune · lepture
< 3.3.0 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-59924
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-59924
Patch
https://github.com/lepture/mistune/commit/1bef343ade163fc3bb95572b15be720084cdb993
Release Notes
https://github.com/lepture/mistune/releases/tag/v3.3.0
Exploit
https://github.com/lepture/mistune/security/advisories/GHSA-r4rv-85jg-w4mf
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