Server-side Request Forgery (SSRF) Affecting astro package, versions <5.17.3>=6.0.0-alpha.0 <6.0.0-beta.7
Threat Intelligence
Snyk has a proof-of-concept or detailed explanation of how to exploit this vulnerability.
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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- published24 Feb 2026
- disclosed23 Feb 2026
- creditRein Daelman,Robbe Verwilghen
Introduced: 23 Feb 2026
NewCVE-2026-25545 (opens in a new tab)How to fix?
Upgrade astro to version 5.17.3, 6.0.0-beta.7 or higher.
Overview
astro is an Astro is a modern site builder with web best practices, performance, and DX front-of-mind.
Affected versions of this package are vulnerable to Server-side Request Forgery (SSRF) in renderError(), when custom prerendered error pages like 404.astro or 500.astro are in use. The resolved URL which is passed to a fetch() call allows redirects. As a result, attackers can access internal network resources and retrieve sensitive response bodies by manipulating the Host header to point to an attacker-controlled server.