CVE-2026-73422

Astro is a web framework for content-driven websites. From 2.9.0 until 7.1.0, Astro's server-side View Transition CSS generator interpolates animation properties into an inline style element without escaping them for CSS and HTML contexts. An attacker-controlled View Transition animation value such as duration can terminate the generated style element and inject arbitrary HTML or JavaScript. The affected code is packages/astro/src/runtime/server/transition.ts; renderTransition passes sheet.toString() into markHTMLString(), while addAnimationProperty serializes duration through toTimeValue() and also handles easing, direction, delay, fillMode, and name. Exploitation requires an on-demand or server-rendered route to pass attacker-controlled data into a View Transition animation definition and can execute arbitrary JavaScript in the affected application's origin, allowing access to sensitive page data and authenticated actions available to the victim. This issue is fixed in version 7.1.0.

CVSS

No CVSS.

References

Link	Resource
https://github.com/withastro/astro/commit/092da560eea77ee63a3e2c583c80d8238544e42b
https://github.com/withastro/astro/pull/17393
https://github.com/withastro/astro/releases/tag/astro@7.1.0
https://github.com/withastro/astro/security/advisories/GHSA-4g3v-8h47-v7g6
https://github.com/withastro/astro/security/advisories/GHSA-4g3v-8h47-v7g6

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-12 21:17

Updated : 2026-09-09 21:02

NVD link : CVE-2026-73422

Mitre link : CVE-2026-73422

CVE.ORG link : CVE-2026-73422

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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