CVE-2026-59727

Astro is a web framework for content-driven websites. In versions 3.10.0 through 7.0.3, 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 <astro-island> element without HTML-escaping it. If a developer reflects attacker-controlled input into one of these directives, an attacker can break out of the attribute and inject arbitrary HTML/JavaScript into the server-rendered output, resulting in reflected cross-site scripting (XSS). Exploitation requires the application developer to have written a non-idiomatic pattern — passing untrusted, request-derived input directly into a transition directive. Astro applications that do not route untrusted input into these directives are unaffected. This issue has been fixed in version 7.0.4.

CVSS

No CVSS.

References

Link	Resource
https://github.com/withastro/astro/commit/7ba0bb1dc7516e88caff9abd7767322af44b0294
https://github.com/withastro/astro/pull/17212
https://github.com/withastro/astro/releases/tag/astro@7.0.4
https://github.com/withastro/astro/security/advisories/GHSA-7pw4-f3q4-r2p2
https://github.com/withastro/astro/security/advisories/GHSA-7pw4-f3q4-r2p2

Configurations

No configuration.

History

28 Jul 2026, 16:19

Type	Values Removed	Values Added
References	~~() https://github.com/withastro/astro/security/advisories/GHSA-7pw4-f3q4-r2p2 -~~	() https://github.com/withastro/astro/security/advisories/GHSA-7pw4-f3q4-r2p2 -

27 Jul 2026, 20:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-27 20:16

Updated : 2026-07-28 16:19

NVD link : CVE-2026-59727

Mitre link : CVE-2026-59727

CVE.ORG link : CVE-2026-59727

JSON object : View

Products Affected

No product.

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

CWE-83

Improper Neutralization of Script in Attributes in a Web Page

CWE-116

Improper Encoding or Escaping of Output

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