Astro: Cross-site scripting via unescaped transition:* directive values on hydrated islands

Summary When a transition:persist, transition:scope, or transition:persist-props directive is applied to a client-hydrated client: component, Astro copied the directive value onto the rendered element without HTML-escaping it. If a developer reflects attacker-controlled input into one of these...

PT-2026-61807

Name of the Vulnerable Software and Affected Versions Astro versions 3.10.0 through 7.0.3 Description Astro fails to HTML-escape values for specific transition directives when applied to client-hydrated components. This occurs within the generateHydrateScript function, where the transition:persis...