FKIE_CVE-2025-69534

Vulnerability from fkie_nvd - Published: 2026-03-05 15:16 - Updated: 2026-03-13 01:25
Severity ?
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Summary
Python-Markdown version 3.8 contain a vulnerability where malformed HTML-like sequences can cause html.parser.HTMLParser to raise an unhandled AssertionError during Markdown parsing. Because Python-Markdown does not catch this exception, any application that processes attacker-controlled Markdown may crash. This enables remote, unauthenticated Denial of Service in web applications, documentation systems, CI/CD pipelines, and any service that renders untrusted Markdown. The issue was acknowledged by the vendor and fixed in version 3.8.1. This issue causes a remote Denial of Service in any application parsing untrusted Markdown, and can lead to Information Disclosure through uncaught exceptions.
References
cve@mitre.orghttps://github.com/Python-Markdown/markdownProduct
cve@mitre.orghttps://github.com/Python-Markdown/markdown/actions/runs/15736122892Product
cve@mitre.orghttps://github.com/Python-Markdown/markdown/issues/1534Exploit, Issue Tracking
af854a3a-2127-422b-91ae-364da2661108http://www.openwall.com/lists/oss-security/2026/03/06/4Mailing List, Third Party Advisory
Impacted products
Vendor Product Version
python-markdown markdown 3.8
To clipboard 

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      "value": "Python-Markdown version 3.8 contain a vulnerability where malformed HTML-like sequences can cause html.parser.HTMLParser to raise an unhandled AssertionError during Markdown parsing. Because Python-Markdown does not catch this exception, any application that processes attacker-controlled Markdown may crash. This enables remote, unauthenticated Denial of Service in web applications, documentation systems, CI/CD pipelines, and any service that renders untrusted Markdown. The issue was acknowledged by the vendor and fixed in version 3.8.1. This issue causes a remote Denial of Service in any application parsing untrusted Markdown, and can lead to Information Disclosure through uncaught exceptions."
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      "value": "Python-Markdown versi\u00f3n 3.8 contiene una vulnerabilidad donde secuencias malformadas similares a HTML pueden hacer que html.parser.HTMLParser genere un AssertionError no manejado durante el an\u00e1lisis de Markdown. Debido a que Python-Markdown no captura esta excepci\u00f3n, cualquier aplicaci\u00f3n que procese Markdown controlado por el atacante puede fallar. Esto permite una denegaci\u00f3n de servicio remota y no autenticada en aplicaciones web, sistemas de documentaci\u00f3n, pipelines de CI/CD y cualquier servicio que renderice Markdown no confiable. El problema fue reconocido por el proveedor y corregido en la versi\u00f3n 3.8.1. Este problema causa una denegaci\u00f3n de servicio remota en cualquier aplicaci\u00f3n que analice Markdown no confiable, y puede llevar a la revelaci\u00f3n de informaci\u00f3n a trav\u00e9s de excepciones no capturadas."
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  "id": "CVE-2025-69534",
  "lastModified": "2026-03-13T01:25:22.277",
  "metrics": {
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          "attackComplexity": "LOW",
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          "confidentialityImpact": "NONE",
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