CVE-2026-59929
Full vulnerability record from the local CVENow database.
Description
Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, the safe_url filter in src/mistune/renderers/html.py blocks only javascript:, vbscript:, file:, and data: schemes, allowing legacy or chained schemes such as feed:, view-source:, jar:, livescript:, mocha:, ms-its:, mk:, and res: to reach rendered href and src attributes and potentially execute script in affected user agents. This issue is fixed in version 3.3.0.
Severity
MEDIUM
CVSS score
6.1
(v3.1)
Vulnerability status
Analyzed
Source identifier
Published
2026-07-08 17:17:28.737000
Last modified
2026-10-25 17:10:00.197000
View original CVE JSON
{
"id": "CVE-2026-59929",
"sourceIdentifier": "[email protected]",
"published": "2026-07-08T17:17:28.737",
"lastModified": "2026-10-25T17:10:00.197",
"vulnStatus": "Analyzed",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, the safe_url filter in src/mistune/renderers/html.py blocks only javascript:, vbscript:, file:, and data: schemes, allowing legacy or chained schemes such as feed:, view-source:, jar:, livescript:, mocha:, ms-its:, mk:, and res: to reach rendered href and src attributes and potentially execute script in affected user agents. This issue is fixed in version 3.3.0."
},
{
"lang": "es",
"value": "Mistune es un analizador de Markdown de Python con renderizadores y complementos. Antes de la 3.3.0, el filtro safe_url en src/mistune/renderers/html.py bloquea solo los esquemas javascript_disabled: , vbscript:, file: y data:, permitiendo que esquemas heredados o encadenados como feed:, view-source:, jar:, livescript:, mocha:, ms-its:, mk: y res: alcancen los atributos href y src renderizados y potencialmente ejecuten scripts en agentes de usuario afectados. Este problema está solucionado en la versión 3.3.0."
}
],
"affected": [
{
"source": "[email protected]",
"affectedData": [
{
"vendor": "lepture",
"product": "mistune",
"versions": [
{
"version": "< 3.3.0",
"status": "affected"
}
]
}
]
}
],
"metrics": {
"cvssMetricV31": [
{
"source": "[email protected]",
"type": "Secondary",
"cvssData": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N",
"baseScore": 6.1,
"baseSeverity": "MEDIUM",
"attackVector": "NETWORK",
"attackComplexity": "LOW",
"privilegesRequired": "NONE",
"userInteraction": "REQUIRED",
"scope": "CHANGED",
"confidentialityImpact": "LOW",
"integrityImpact": "LOW",
"availabilityImpact": "NONE"
},
"exploitabilityScore": 2.8,
"impactScore": 2.7
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"timestamp": "2026-07-09T14:21:09.261426Z",
"id": "CVE-2026-59929",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "partial"
}
],
"role": "CISA Coordinator",
"version": "2.0.3"
}
}
]
},
"weaknesses": [
{
"source": "[email protected]",
"type": "Secondary",
"description": [
{
"lang": "en",
"value": "CWE-79"
},
{
"lang": "en",
"value": "CWE-184"
}
]
}
],
"configurations": [
{
"nodes": [
{
"operator": "OR",
"negate": false,
"cpeMatch": [
{
"vulnerable": true,
"criteria": "cpe:2.3:a:mistune_project:mistune:*:*:*:*:*:*:*:*",
"versionEndExcluding": "3.3.0",
"matchCriteriaId": "63E1B933-D2E2-44EF-A56C-94483300845B"
}
]
}
]
}
],
"references": [
{
"url": "https://github.com/lepture/mistune/commit/c7101fcbb6e8790e8e39157c5ca2238fc6dd6cbc",
"source": "[email protected]",
"tags": [
"Patch"
]
},
{
"url": "https://github.com/lepture/mistune/releases/tag/v3.3.0",
"source": "[email protected]",
"tags": [
"Release Notes"
]
},
{
"url": "https://github.com/lepture/mistune/security/advisories/GHSA-qfrw-5rxm-mhh2",
"source": "[email protected]",
"tags": [
"Exploit",
"Third Party Advisory"
]
}
]
}