Vulnerability Description
Astro is a web framework. Prior to version 9.5.4, Server-Side Rendered pages that return an error with a prerendered custom error page (eg. `404.astro` or `500.astro`) are vulnerable to SSRF. If the `Host:` header is changed to an attacker's server, it will be fetched on `/500.html` and they can redirect this to any internal URL to read the response body through the first request. An attacker who can access the application without `Host:` header validation (eg. through finding the origin IP behind a proxy, or just by default) can fetch their own server to redirect to any internal IP. With this they can fetch cloud metadata IPs and interact with services in the internal network or localhost. For this to be vulnerable, a common feature needs to be used, with direct access to the server (no proxies). Version 9.5.4 fixes the issue.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Astro | \@Astrojs\/Node | < 9.5.4 |
Related Weaknesses (CWE)
References
- https://github.com/withastro/astro/commit/e01e98b063e90d274c42130ec2a60cc0966622Patch
- https://github.com/withastro/astro/releases/tag/%40astrojs%2Fnode%409.5.4ProductRelease Notes
- https://github.com/withastro/astro/security/advisories/GHSA-qq67-mvv5-fw3gExploitThird Party Advisory
FAQ
What is CVE-2026-25545?
CVE-2026-25545 is a vulnerability with a CVSS score of 8.6 (HIGH). Astro is a web framework. Prior to version 9.5.4, Server-Side Rendered pages that return an error with a prerendered custom error page (eg. `404.astro` or `500.astro`) are vulnerable to SSRF. If the `...
How severe is CVE-2026-25545?
CVE-2026-25545 has been rated HIGH with a CVSS base score of 8.6/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-25545?
Check the references section above for vendor advisories and patch information. Affected products include: Astro \@Astrojs\/Node.