CVE-2026-115354

Mistune before 3.3.0 contains a path traversal vulnerability in the opt-in Include directive that allows attackers to read local files by supplying relative or absolute include paths. Attackers who submit Markdown rendered via Markdown.read() can disclose files such as /etc/passwd and inject unescaped HTML or script content into rendered output.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/lepture/mistune/security/advisories/GHSA-jhcm-5rpf-j3wv
https://www.vulncheck.com/advisories/mistune-before-3.3.0-arbitrary-local-file-read-via-include-directive
https://github.com/lepture/mistune/security/advisories/GHSA-jhcm-5rpf-j3wv

Configurations

No configuration.

History

29 Oct 2026, 04:18

Type	Values Removed	Values Added
References	~~() https://github.com/lepture/mistune/security/advisories/GHSA-jhcm-5rpf-j3wv -~~	() https://github.com/lepture/mistune/security/advisories/GHSA-jhcm-5rpf-j3wv -

22 Oct 2026, 19:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-22 19:17

Updated : 2026-10-29 04:18

NVD link : CVE-2026-115354

Mitre link : CVE-2026-115354

CVE.ORG link : CVE-2026-115354

JSON object : View

Products Affected

No product.

CWE

CWE-22

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

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