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CVE-2026-115350medium6.1

Mistune before 3.3.0 Stored XSS via Include Directive HTML Files

Impact

Mistune before 3.3.0 has a cross-site scripting vulnerability via the Include directive, allowing attackers with access to plant an HTML file to execute stored scripts when escape=False is set. The vulnerability affects versions less than 3.3.0. Attackers need to be able to plant an HTML file readable by the renderer.

Summarized by @cf/meta/llama-3.3-70b-instruct-fp8-fast. Verify details against the original sources.

Affected packages

This source has no supported package-version data for matching. You can read the advisory here, but this record alone cannot power a dependency check.

Affected products

Vendor version evidence. Product records are separate from automatic dependency matching.

lepture · VulnCheck

mistune

2 ranges
VulnCheck version evidence

Package identity

pkg:pypi/mistuneExplore mistune →

Identity supplied by VulnCheck. Version matching requires compatible range evidence.

Compare with this publisher’s ranges. This does not inspect your installation.

affected

0 → before 3.3.0

semver versions

unaffected

3.3.0

semver versions

unknown

Other versions: unaffected

Original source description

Mistune before 3.3.0 contains a cross-site scripting vulnerability in the Include directive that emits included .html, .xhtml, or .htm file content as raw block_html tokens. Attackers who can plant an HTML file readable by the renderer can reference it via an include directive, combined with path traversal, to execute stored scripts when escape=False is set.

Inside the record

Evidence available

Package identity
Version evidence
Remediation guidance · not supplied
Weakness classification
Additional publishers

Describes the evidence in this view, not whether the product is safe.

Original records

CVE-2026-115350

View the latest unmodified CVE JSON from the official source. It may be newer than this imported page.

cve.new JSON →

Underlying weaknesses

The source’s classification of what caused the vulnerability.

CWE-79 ↗

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

VulnCheck

Related →

Environment requirements

These conditions apply together as specified by the publisher. A matching product name alone does not establish exposure.

VulnCheck · platform conditions

Any condition may hold

Vulnerable product

cpe:2.3:a:mistune_project:mistune:*:*:*:*:*:*:*:*

Before: 3.3.0

Original applicability statements
[
  {
    "nodes": [
      {
        "operator": "OR",
        "negate": false,
        "cpeMatch": [
          {
            "vulnerable": true,
            "criteria": "cpe:2.3:a:mistune_project:mistune:*:*:*:*:*:*:*:*",
            "versionEndExcluding": "3.3.0"
          }
        ]
      }
    ]
  }
]
Contributing organizations · 2
VulnCheck

Assigning organization

2026-10-22
CISA-ADP

Additional data publisher

2026-10-29

What changed

Follow changes
No substantive changes have been recorded here yet. History starts when cve.new observes a change after tracking is enabled; earlier edits are not reconstructed.

Large field values are marked as truncated previews. Original source snapshots remain retained.

References

2 sources
github.com/lepture/mistune/security/advisories/GHSA-96vr-jm8v-g22j
vendor-advisoryVulnCheck
www.vulncheck.com/advisories/mistune-before-3.3.0-stored-xss-via-include-directive-html-files
third-party-advisoryVulnCheck