GHSA-5ff5-9fcw-vg88 · Severity: medium · Ecosystem: npm — Astro's `X-Forwarded-Host` is reflected without validation
Astro is a web framework. Prior to version 5.14.2, Astro reflects the value in `X-Forwarded-Host` in output when using `Astro.url` without any validation. It is common for web servers such as nginx to route requests via the `Host` header, and forward on other request headers. As such as malicious request can be sent with both a `Host` header and an `X-Forwarded-Host` header where the values do not match and the `X-Forwarded-Host` header is malicious. Astro will then return the malicious value. This could result in any usages of the `Astro.url` value in code being manipulated by a request. For example if a user follows guidance and uses `Astro.url` for a canonical link the canonical link can be manipulated to another site. It is theoretically possible that the value could also be used as a login/registration or other form URL as well, resulting in potential redirecting of login credentials to a malicious party. As this is a per-request attack vector the surface area would only be to the malicious user until one considers that having a caching proxy is a common setup, in which case any page which is cached could persist the malicious value for subsequent users. Many other frameworks have an allowlist of domains to validate against, or do not have a case where the headers are reflected to avoid such issues. This could affect anyone using Astro in an on-demand/dynamic rendering mode behind a caching proxy. Version 5.14.2 contains a fix for the issue.
Conclusion & alert: CVE-2025-61925 is rated Exploit Available (50/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.06%). Core evidence: 1 public exploit reference(s) are indexed (Exploit-DB). Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
| EDB-ID | Source | Kind | Published | Link |
|---|---|---|---|---|
| — | nvd_ref | exploit_tag | Exploit-DB ↗ |
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-04-17 | 0.02% | 0.06% | +0.04% |
| 2 | 2025-11-21 | 0.06% | 0.02% | -0.04% |
| 3 | 2025-11-18 | — | 0.06% | — |
Full EPSS history (6 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 6.5 | 3.1 | MEDIUM |
|
3.9 | 2.5 | [email protected] |
GHSA-5ff5-9fcw-vg88 · Severity: medium · Ecosystem: npm — Astro's `X-Forwarded-Host` is reflected without validation
| URL | Tags |
|---|---|
| https://github.com/Chisnet/minimal_dynamic_astro_server | Product |
| https://github.com/withastro/astro/security/advisories/GHSA-5ff5-9fcw-vg88 | Exploit Third Party Advisory |