Bug 2481733 (CVE-2026-44708)

Summary: CVE-2026-44708 python-mistune: Mistune: Cross-Site Scripting via improper HTML escaping in math plugin
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: anthomas, ehelms, ggainey, jkoehler, juwatts, lphiri, mhulan, nmoumoul, osousa, pcreech, rchan, rjohnson, smallamp, tmalecek
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in Mistune, a Python Markdown parser. The mistune math plugin improperly handles user-supplied content, such as inline and block math, by directly embedding it into the HTML output without proper HTML escaping. This vulnerability, which can lead to Cross-Site Scripting (XSS), allows a remote attacker to inject malicious scripts into a web page, potentially leading to information disclosure or unauthorized actions when a user interacts with the affected content.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-05-26 22:02:32 UTC
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.