---
id: CVE-2026-115355
title: Mistune before 3.3.0 Path Traversal and XSS via Include Directive
summary: >-
  Mistune before 3.3.0 contains a path traversal vulnerability in the Include
  directive that allows attackers to read arbitrary files by supplying ../
  sequences in include paths. Attackers can also inject HTML through unescaped
  error messa…
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N'
cvssSource: cna
cwe:
  - CWE-22
vendor: lepture
product: mistune
affected:
  - mistune < 3.3.0
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-10-29T13:46:05.214120Z'
published: '2026-10-22'
updated: '2026-10-29'
sourceUpdated: '2026-10-29T13:48:43.278Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-115355'
references:
  - url: 'https://github.com/lepture/mistune/security/advisories/GHSA-h7ww-273w-6cm8'
    label: GitHub Security Advisory (GHSA-h7ww-273w-6cm8)
  - url: >-
      https://www.vulncheck.com/advisories/mistune-before-3.3.0-path-traversal-and-xss-via-include-directive
    label: >-
      VulnCheck Advisory: Mistune before 3.3.0 Path Traversal and XSS via
      Include Directive
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-115355'
  - url: >-
      https://github.com/lepture/mistune/commit/1bef343ade163fc3bb95572b15be720084cdb993
  - url: 'https://github.com/lepture/mistune'
  - url: 'https://github.com/lepture/mistune/releases/tag/v3.3.0'
  - url: 'https://github.com/advisories/GHSA-h7ww-273w-6cm8'
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-115355.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-115355'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2559366'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-115355'
tags:
  - cve.org
  - osv
  - pip
  - ghsa
  - csaf
  - vex
  - red-hat
epss: 0.00461
epssPercentile: 0.39943
aliases:
  - GHSA-h7ww-273w-6cm8
ecosystem: pip
patched:
  - mistune 3.3.0
ingestedAt: '2026-10-22T22:00:50.398Z'
---

## Overview

Mistune before 3.3.0 contains a path traversal vulnerability in the Include directive that allows attackers to read arbitrary files by supplying ../ sequences in include paths. Attackers can also inject HTML through unescaped error messages and included file contents to perform cross-site scripting even when escape=True is set.

## Affected

- `mistune < 3.3.0`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Package advisory (CVE-2026-115355)

Affected packages:

- `mistune < 3.3.0`

Patched in:

- `mistune 3.3.0`

Source: https://osv.dev/vulnerability/GHSA-h7ww-273w-6cm8

## Vendor advisories

- **Red Hat VEX** · Important · affected: Red Hat OpenShift AI (RHOAI), Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat OpenShift AI (RHOAI), Red Hat OpenShift Container Platform 4 · updated 2026-10-23 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-115355.json)