# CVE-2025-55207: Astro Node adapter open redirect via trailing slash handling

Source: https://junglewise.ai/threats/cve-2025-55207-astro-node-adapter-open-redirect-via-trailing-slash-handling  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2025-08-15. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2025-55207 · Severity: medium · CVSS 4 · Published 2025-08-15

The Astro Node deployment adapter is vulnerable to open redirect attacks when configured with trailingSlash set to "always". An attacker can craft a malicious link with a double slash (e.g., //astro.build/press) that tricks the vulnerable server into redirecting users to an external website, enabling phishing, credential theft, or malware distribution attacks. No authentication is required to exploit this vulnerability.

Technologies: [@astrojs/node (npm)](https://junglewise.ai/threats/technologies/astrojs-node). Vendors: [Astro](https://junglewise.ai/threats/vendors/astro), [npm](https://junglewise.ai/threats/vendors/npm).

## Quick answers

**Is CVE-2025-55207 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2025-55207 being exploited in the wild.

**How severe is CVE-2025-55207?** Medium severity, with a CVSS score of 4, published 15 August 2025.

**Which products and versions are affected?** Astro Node adapter <= 9.4.0; @astrojs/node (npm) SEMVER:introduced=0,fixed=9.4.1.

**Is there a fix for CVE-2025-55207?** Yes. @astrojs/node (npm): upgrade to 9.4.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2025-55207 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2025-55207?** Check whether you run Astro Node adapter or @astrojs/node (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- @astrojs/node (npm): upgrade to 9.4.1 or later

  ```sh
  npm install @astrojs/node@9.4.1
  ```


## Technical details

This is an open redirect vulnerability (CWE-601) in the @astrojs/node adapter's trailing slash normalization logic. When the adapter is configured in standalone mode with trailingSlash set to "always", URLs with protocol-relative paths (double slashes, e.g., //example.com/path) are not properly sanitized before being used in redirect responses. An unauthenticated attacker can exploit this via network access by crafting a specially formatted URL (https://victim.com//attacker.com/path) that the server incorrectly normalizes and redirects to the attacker's domain. The vulnerability affects @astrojs/node versions up to 9.4.0 and is fixed in version 9.4.1.

## Affected products

- Astro Node adapter <= 9.4.0

## Identifiers

- CVE-2025-55207
- GHSA-9x9c-ghc5-jhw9

## Timeline

- 2025-08-15: disclosed
- 2025-08-15: patched: Fixed in @astrojs/node 9.4.1

## References

- [https://github.com/withastro/astro/security/advisories/GHSA-9x9c-ghc5-jhw9](https://github.com/withastro/astro/security/advisories/GHSA-9x9c-ghc5-jhw9)

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