Use GitHub's private vulnerability reporting on this repository ("Security" tab, "Report a vulnerability"). Do not open a public issue for a bypass.

Please include the input (Markdown or HTML), the mode and policy overrides, the browser, and what the rendered DOM or network did. A failing test in packages/core/test is the best report.

You will get an acknowledgement within 48 hours and a fix or a decision within 30 days. Credit goes to the reporter in the advisory and the changelog unless you prefer otherwise.

• A payload that executes script, or reaches an on* attribute, <script>, <style>, a form control or a forbidden element in any mode.
• A URL that reaches the DOM with a scheme outside allowedSchemes, or an image request to a host outside imageHosts in strict or balanced mode.
• A request made from a streamed buffer to a URL that was not yet complete.
• A Trusted Types violation raised by the core under require-trusted-types-for 'script'.

Heuristics (urlHeuristics) and the sink denylist are best-effort layers behind the host allowlist; a bypass of them alone is a bug report, not an advisory.

The latest minor release on npm.

Findings in other renderers or frameworks discovered while building this library are reported to those projects privately and are published here only after a fix or the agreed disclosure date.