CVE-2025-23207: \htmlData does not validate attribute names in KaTeX
Impact KaTeX users who render untrusted mathematical expressions with renderToString could encounter malicious input using \htmlData that runs arbitrary JavaScript, or generate invalid HTML.
Patches Upgrade to KaTeX v0.16.21 to remove this vulnerability.
Workarounds - Avoid use of or turn off the trust option, or set it to forbid \htmlData commands. - Forbid inputs containing the substring "\\htmlData". - Sanitize HTML output from KaTeX.
Details \htmlData did not validate its attribute name argument, allowing it to generate invalid or malicious HTML that runs scripts.
For more information If you have any questions or comments about this advisory:
- Open an issue or security advisory in the KaTeX repository - Email us at katex-security@mit.edu
Other sources
KaTeX is a fast, easy-to-use JavaScript library for TeX math rendering on the web. KaTeX users who render untrusted mathematical expressions with renderToString could encounter malicious input using \htmlData that runs arbitrary JavaScript, or generate invalid HTML. Users are advised to upgrade to KaTeX v0.16.21 to remove this vulnerability. Users unable to upgrade should avoid use of or turn off the trust option, or set it to forbid \htmlData commands, forbid inputs containing the substring "\\htmlData" and sanitize HTML output from KaTeX.
— NVD
Affected Software
Remediation
Event History
Frequently Asked Questions
What is the severity of CVE-2025-23207?
CVE-2025-23207 is considered a high-severity vulnerability due to the potential for executing arbitrary JavaScript from untrusted inputs.
How do I fix CVE-2025-23207?
To fix CVE-2025-23207, upgrade to KaTeX version 0.16.21 or later.
Who is affected by CVE-2025-23207?
Users of KaTeX who render untrusted mathematical expressions with renderToString are affected by CVE-2025-23207.
What kind of attacks are possible with CVE-2025-23207?
CVE-2025-23207 allows attackers to run arbitrary JavaScript or generate invalid HTML through malicious input using \htmlData.
Are there any workarounds for CVE-2025-23207?
While upgrading is the best solution for CVE-2025-23207, avoiding the use of renderToString with untrusted inputs may serve as a temporary workaround.