Vulnerability · Published Aug 8, 2025 · Assigned by GitHub_M
CVE-2025-54793Astro: Duplicate trailing slash feature can lead to Open Redirects
Medium 5.5
In plain English
A medium-severity open redirect in astro from withastro. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.7% (higher than 53% of all known vulnerabilities). Ready-made attack tooling exists: Nuclei, public proof-of-concept code. Fixed versions are available - upgrade the affected package.
Official description
Astro is a web framework for content-driven websites. In versions 5.2.0 through 5.12.7, there is an Open Redirect vulnerability in the trailing slash redirection logic when handling paths with double slashes. This allows an attacker to redirect users to arbitrary external domains by crafting URLs such as https://mydomain.com//malicious-site.com/. This increases the risk of phishing and other social engineering attacks. This affects sites that use on-demand rendering (SSR) with the Node or Cloudflare adapters. It does not affect static sites, or sites deployed to Netlify or Vercel. This issue is fixed in version 5.12.8. To work around this issue at the network level, block outgoing redirect responses with a Location header value that starts with `//`.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| npm | astro | 5.12.8 | GHSA-cq8c-xv66-36gw |
Affected products (as reported)
Weakness: CWE-601 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:P