{"apiVersion":"1.0","identifier":"CVE-2026-73422","description":"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.","publishedAt":"2026-08-12T21:17:41","lastModifiedAt":"2026-08-14T23:16:32","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-73422","cvssScore":5.3,"cvssVector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","epssProbability":0.00311,"riskScore":0.54,"affectedProduct":"Astro","affectedVersions":">=2.9.0,<7.1.0","vulnerabilityType":"Library","operatingSystems":[],"links":{"self":"https://www.redsauce.net/api/cves/CVE-2026-73422","webPages":{"es":"https://www.redsauce.net/es/cves/CVE-2026-73422","en":"https://www.redsauce.net/en/cves/CVE-2026-73422","fr":"https://www.redsauce.net/fr/cves/CVE-2026-73422","pt":"https://www.redsauce.net/pt/cves/CVE-2026-73422","de":"https://www.redsauce.net/de/cves/CVE-2026-73422","sk":"https://www.redsauce.net/sk/cves/CVE-2026-73422","el":"https://www.redsauce.net/el/cves/CVE-2026-73422"},"source":"https://nvd.nist.gov/vuln/detail/CVE-2026-73422"}}