CVE-2026-44897
MEDIUMDescription
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 fixed in 3.2.1.
How to fix
Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.
CVSS v3 Vector
Exploitability
Impact
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N/E:U
Exploit Intelligence
Low risk: more likely to be exploited than 14% of all known CVEs.
References
Related Vulnerabilities
Other CWE-79 (Cross-Site Scripting (XSS)) vulnerabilities, ordered by exploit likelihood. View all
| CVE | Severity | CVSS | EPSS | Exploited | Fix |
|---|---|---|---|---|---|
| CVE-2020-11022 | Medium | 6.9 | 99% | - | Fix |
| CVE-2019-3929 | Critical | 9.8 | 99% | KEV | Fix |
| CVE-2020-9496 | Medium | 6.1 | 99% | - | - |
| CVE-2023-28341 | Medium | 6.1 | 99% | - | Fix |
| CVE-2018-12998 | Medium | 6.1 | 98% | - | - |
| CVE-2025-4123 | High | 7.6 | 98% | - | Fix |
Embed a live status badge for CVE-2026-44897
Markdown
[](https://tridentstack.com/cve/CVE-2026-44897)HTML
<a href="https://tridentstack.com/cve/CVE-2026-44897"><img src="https://tridentstack.com/cve/badge/CVE-2026-44897.svg" alt="CVE-2026-44897"></a>Find and fix vulnerabilities across your fleet
TridentStack Control continuously scans your Windows, macOS, and Linux fleet for known vulnerabilities, prioritizes them by severity and active exploitation, and patches them automatically.
Start freeThis product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-05-28.