4.7
Medium
CVE-2026-44899 Mistune is a Python Markdown parser with renderers and plugins
Description
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 without escaping. This vulnerability is fixed in 3.2.1.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| mistune 3.2 | earliest → < 3.2.1 | 3.2.1 |
References
- github.com github.com
- github.com github.com
Timeline
- Published
- Last modified
Other CVEs of mistune
The 28 CVEs of mistune →
CVE-2026-121437
Mistune from 3.3.0 before 3.3.4 contains a denial of service vulnerability that allows remote attackers to exhaust CPU…
8.7
High
CVE-2026-121438
Mistune before 3.3.3 contains a denial of service vulnerability in InlineParser.parse_link that allows attackers to…
6.9
Medium
CVE-2026-115354
Mistune before 3.3.0 contains a path traversal vulnerability in the opt-in Include directive that allows attackers to…
7.1
High
CVE-2026-115355
Mistune before 3.3.0 contains a path traversal vulnerability in the Include directive that allows attackers to read…
8.7
High