High severity · published Oct 22, 2026
CVE-2026-115353
Mistune before 3.3.0 Path Traversal via include Directive
New
8.6
CVSS
0.4%
EPSS
No
On KEV
Description
Mistune before 3.3.0 contains a path traversal vulnerability in the RST include directive that allows attackers to read arbitrary files by supplying relative or absolute paths. Attackers can submit markdown containing include directives referencing ../ sequences or absolute paths to embed sensitive files like credentials or environment data in rendered HTML.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
None
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 33% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MI
mistune · lepture
before 3.3.0 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-115353
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-115353
github.com
https://github.com/lepture/mistune/security/advisories/GHSA-9jjx-3hq3-hx4j
www.vulncheck.com
https://www.vulncheck.com/advisories/mistune-before-3.3.0-path-traversal-via-include-directive
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