GHSA-cg87-wmx4-v546 KaTeX \htmlData does not validate attribute names

• npm katex: >= 0.12.0, < 0.16.21 → fixed in 0.16.21

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 [email protected]