PT-2026-49731 · Astro · Astro

Floudeciel · CVE-2026-50146 · Published 2026-06-16 · Updated 2026-06-22

Positive Technologies (AI Summary)

CVSS v3.1

7.1

High

Base vector

AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:H/A:N

Name of the Vulnerable Software and Affected Versions Astro versions prior to 6.3.3

Description When a component utilizes a client:* directive, the software inserts named slot content into a data-astro-template attribute without performing HTML escaping on the slot name. This allows an attacker to break out of the attribute context and inject arbitrary HTML, leading to reflected Cross-Site Scripting (XSS) during Server-Side Rendering (SSR), which is the process of rendering web pages on the server instead of the browser.

Recommendations Update to version 6.3.3.

Exploit

Fix

XSS

Weakness Enumeration

CWE-79

CWE-80

Related Identifiers

CVE-2026-50146

GHSA-8HV8-536X-4WQP

Affected Products

Astro

References · 6

• 🔥 https://github.com/withastro/astro/security/advisories/GHSA-8hv8-536x-4wqp · Exploit
• 🔥 https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/50xxx/CVE-2026-50146.json · Exploit
• https://nvd.nist.gov/vuln/detail/CVE-2026-50146 · Security Note
• https://osv.dev/vulnerability/CVE-2026-50146 · Vendor Advisory
• https://osv.dev/vulnerability/GHSA-8hv8-536x-4wqp · Vendor Advisory
• https://github.com/withastro/astro · Note