Exploiting XSS in hidden inputs and meta tags
Summary: PortSwigger researcher Gareth Heyes showed that Chrome's new HTML popover functionality, which fires the ontoggle and onbeforetoggle events without JavaScript, can be used to execute XSS inside hidden inputs and meta elements. Heyes found that a single injection point suffices when the injected element shares an id with an existing popover target and appears before it, and Mario Heiderich and Mathias Karlsson extended the technique to hidden inputs and meta tags respectively.
What's compelling: Hidden inputs and meta tags are heavily restricted elements where most XSS events will not fire, so teams that treat injection there as low-risk now have a working click-triggered path to script execution, and the onbeforetoggle event is unlikely to be caught by attribute-based blocklists.
Read the original at PortSwigger Research ↗
- Topics
- Vulnerabilities & Patching
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