CVE-2026-59729

Astro is a web framework for content-driven websites. Versions prior to 7.0.6 are vulnerable to XSS through unescaped spread attribute names in renderHTMLElement. The fix for CVE-2026-54298 (GHSA-jrpj-wcv7-9fh9) added an INVALID_ATTR_NAME_CHAR guard to addAttribute() so that spread-prop attribute names containing "' >/= or whitespace are dropped. A second attribute-rendering path, renderHTMLElement() in packages/astro/src/runtime/server/render/dom.ts, has its own inline attribute loop that does not go through addAttribute() and was not updated. It interpolates the attribute name unescaped and only escapes the value, so untrusted prop keys spread onto a native-HTMLElement-subclass component can still break out of the attribute context. This issue has been fixed in version 7.0.6.

CVSS

No CVSS.

References

Link	Resource
https://github.com/withastro/astro/commit/5240e26c9dd91f9bc7140dcfacdb48d5a132830d
https://github.com/withastro/astro/pull/17251
https://github.com/withastro/astro/releases/tag/astro@7.0.6
https://github.com/withastro/astro/security/advisories/GHSA-f48w-9m4c-m7f5
https://github.com/withastro/astro/security/advisories/GHSA-f48w-9m4c-m7f5

Configurations

No configuration.

History

No history.

Information

Published : 2026-07-27 20:16

Updated : 2026-07-28 16:17

NVD link : CVE-2026-59729

Mitre link : CVE-2026-59729

CVE.ORG link : CVE-2026-59729

JSON object : View

Products Affected

No product.

CWE

CWE-79

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

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