CVE-2026-50146

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 v3 7.1 HIGH

7.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 4.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/withastro/astro/security/advisories/GHSA-8hv8-536x-4wqp	Exploit Mitigation Vendor Advisory
https://github.com/withastro/astro/security/advisories/GHSA-8hv8-536x-4wqp	Exploit Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:astro:astro:*:*:*:*:*:node.js:*:*

History

23 Jun 2026, 15:16

Type	Values Removed	Values Added
References	~~() https://github.com/withastro/astro/security/advisories/GHSA-8hv8-536x-4wqp - Exploit, Mitigation, Vendor Advisory~~	() https://github.com/withastro/astro/security/advisories/GHSA-8hv8-536x-4wqp - Exploit, Mitigation, Vendor Advisory

22 Jun 2026, 20:37

Type	Values Removed	Values Added
CPE		cpe:2.3:a:astro:astro::::::node.js::*
First Time		Astro Astro astro
References	~~() https://github.com/withastro/astro/security/advisories/GHSA-8hv8-536x-4wqp -~~	() https://github.com/withastro/astro/security/advisories/GHSA-8hv8-536x-4wqp - Exploit, Mitigation, Vendor Advisory

22 Jun 2026, 19:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-22 19:17

Updated : 2026-06-23 15:16

NVD link : CVE-2026-50146

Mitre link : CVE-2026-50146

CVE.ORG link : CVE-2026-50146

JSON object : View

Products Affected

astro

astro

CWE

CWE-80

Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS)

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