CVE-2026-44708: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in lepture mistune
Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.2.1, the mistune math plugin renders inline math ($...$) and block math ($$...$$) by concatenating the raw user-supplied content directly into the HTML output without any HTML escaping. This occurs even when the parser is explicitly created with escape=True, which is supposed to guarantee that all user-controlled text is sanitised before reaching the DOM. This vulnerability is fixed in 3.2.1.
AI Analysis
Technical Summary
Mistune is a Python Markdown parser with support for renderers and plugins, including a math plugin that renders inline and block math expressions. In versions before 3.2.1, the math plugin inserts user-supplied content directly into HTML output without escaping, violating the expected behavior of escape=True which should sanitize user input. This improper neutralization of input during web page generation (CWE-79) allows an attacker to inject malicious scripts, resulting in a cross-site scripting vulnerability. The vulnerability has a CVSS 3.1 base score of 6.1, indicating a medium severity level. The vulnerability is resolved in version 3.2.1 of mistune.
Potential Impact
Successful exploitation of this vulnerability could allow an attacker to execute arbitrary scripts in the context of the victim's browser when viewing content rendered by the vulnerable mistune math plugin. This can lead to limited confidentiality and integrity impacts such as theft of user data or manipulation of displayed content. There is no indication of availability impact. No known exploits in the wild have been reported as of the publication date.
Mitigation Recommendations
Upgrade mistune to version 3.2.1 or later, where this vulnerability is fixed. Since the vulnerability is addressed in this official release, applying this update is the recommended remediation. Patch status is confirmed fixed in 3.2.1. No additional mitigations are specified or required.
CVE-2026-44708: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in lepture mistune
Description
Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.2.1, the mistune math plugin renders inline math ($...$) and block math ($$...$$) by concatenating the raw user-supplied content directly into the HTML output without any HTML escaping. This occurs even when the parser is explicitly created with escape=True, which is supposed to guarantee that all user-controlled text is sanitised before reaching the DOM. This vulnerability is fixed in 3.2.1.
CVSS v3.1
Score 6.1medium
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Mistune is a Python Markdown parser with support for renderers and plugins, including a math plugin that renders inline and block math expressions. In versions before 3.2.1, the math plugin inserts user-supplied content directly into HTML output without escaping, violating the expected behavior of escape=True which should sanitize user input. This improper neutralization of input during web page generation (CWE-79) allows an attacker to inject malicious scripts, resulting in a cross-site scripting vulnerability. The vulnerability has a CVSS 3.1 base score of 6.1, indicating a medium severity level. The vulnerability is resolved in version 3.2.1 of mistune.
Potential Impact
Successful exploitation of this vulnerability could allow an attacker to execute arbitrary scripts in the context of the victim's browser when viewing content rendered by the vulnerable mistune math plugin. This can lead to limited confidentiality and integrity impacts such as theft of user data or manipulation of displayed content. There is no indication of availability impact. No known exploits in the wild have been reported as of the publication date.
Mitigation Recommendations
Upgrade mistune to version 3.2.1 or later, where this vulnerability is fixed. Since the vulnerability is addressed in this official release, applying this update is the recommended remediation. Patch status is confirmed fixed in 3.2.1. No additional mitigations are specified or required.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-05-07T17:07:09.318Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a170b61e29bf47b50c90912
Added to database: 05/27/2026, 15:18:57 UTC
Last enriched: 05/27/2026, 15:49:34 UTC
Last updated: 07/31/2026, 19:22:59 UTC
Views: 113
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