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CVE-2026-50146

CVE-2026-50146 · Astro: Reflected XSS via unescaped slot name

This page contains facts from public vulnerability sources. Check the original advisory before updating.

Astro is a web framework. Prior to 6.3.3, when a component uses a client:* directive, Astro inserts named slot content into a data-astro-template attribute without HTML escaping the slot name allowing an attacker to break out of the attribute context and inject arbitrary HTML, resulting in reflected XSS during SSR. This vulnerability is fixed in 6.3.3.

CVSS 7.1 · High · EPSS 0.3% · Fix available

Published
Updated

Stack: node

Affected products and versions

  • astro

    Versions
    • < 6.3.3: Affected

    No fix published

  • astro npm

    Affected ranges
    • SEMVER: < 6.3.3

    Update to 6.3.3

Original sources

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