This page lists publicly disclosed CVE vulnerabilities affecting mistune_project mistune (linked via NVD CPE). Each row includes severity scores, summaries, and publication dates to help identify and analyze security issues.
| CVE | Summary | Source | Max CVSS | EPSS % | Published | Updated |
|---|---|---|---|---|---|---|
| CVE-2026-44899 | Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.2.1, the Image directive plugin validates the :width: and :height: options with a regex compiled as _num_re = re.compile(r"^\d+(?:\.\d*)?"). When the validated value is not a plain integer, render_block_image() inserts it directly into a style="width:...;" or style="height:...;" attribute. Because the value was accepted by the prefix-only regex, any CSS after the leading digits reaches the style= attribute verbatim and wi | [email protected] | 4.7 | 0.03% | 2026-05-26 | 2026-05-28 |
| CVE-2026-44898 | Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.2.1, render_toc_ul() builds a <ul> table-of-contents tree from a list of (level, id, text) tuples. Both the id value (used as href="#<id>") and the text value (used as the visible link label) are inserted into <a> tags via a plain Python format string — with no HTML escaping applied to either value. When heading IDs are derived from user-supplied heading text (the standard use-case for readable slug anchors), an attacker | [email protected] | 6.1 | 0.03% | 2026-05-26 | 2026-05-28 |
| CVE-2026-44897 | Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.2.1, HTMLRenderer.heading() builds the opening <hN> tag by string-concatenating the id attribute value directly into the HTML — with no call to escape(), safe_entity(), or any other sanitisation function. A double-quote character " in the id value terminates the attribute, allowing an attacker to inject arbitrary additional attributes (event handlers, src=, href=, etc.) into the heading element. This vulnerability is fixe | [email protected] | 6.1 | 0.03% | 2026-05-26 | 2026-05-28 |
| CVE-2026-44896 | Mistune is a Python Markdown parser with renderers and plugins. In 3.2.0 and realier, in src/mistune/directives/image.py, the render_figure() function concatenates figclass and figwidth options directly into HTML attributes without escaping. This allows attribute injection and XSS even when HTMLRenderer(escape=True) is used, because these values bypass the inline renderer. | [email protected] | 5.3 | 0.05% | 2026-05-26 | 2026-05-28 |
| CVE-2026-44708 | 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. | [email protected] | 6.1 | 0.03% | 2026-05-26 | 2026-05-28 |
| CVE-2022-34749 | In mistune through 2.0.2, support of inline markup is implemented by using regular expressions that can involve a high amount of backtracking on certain edge cases. This behavior is commonly named catastrophic backtracking. | [email protected] | 7.5 | 0.49% | 2022-07-25 | 2024-11-21 |
| CVE-2017-16876 | Cross-site scripting (XSS) vulnerability in the _keyify function in mistune.py in Mistune before 0.8.1 allows remote attackers to inject arbitrary web script or HTML by leveraging failure to escape the "key" argument. | [email protected] | 6.1 | 0.23% | 2017-12-29 | 2026-05-13 |
| CVE-2017-15612 | mistune.py in Mistune 0.7.4 allows XSS via an unexpected newline (such as in java\nscript:) or a crafted email address, related to the escape and autolink functions. | [email protected] | 6.1 | 0.12% | 2017-10-19 | 2026-05-13 |