What’s Vulnerable › Vulnerabilities
CVE-2026-33769: Astro: Remote allowlist bypass via unanchored matchPathname wildcard
- Severity: medium (CVSS 5.3 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.3% probability of exploitation in the next 30 days
- Public exploit or detection template: yes
- Published: 2026-03-24 · updated 2026-06-17
- Weakness: CWE-20
Description
Astro is a web framework. From version 2.10.10 to before version 5.18.1, this issue concerns Astro's remotePatterns path enforcement for remote URLs used by server-side fetchers such as the image optimization endpoint. The path matching logic for /* wildcards is unanchored, so a pathname that contains the allowed prefix later in the path can still match. As a result, an attacker can fetch paths outside the intended allowlisted prefix on an otherwise allowed host. This issue has been patched in version 5.18.1.
Affected products
- withastro astro: from 2.10.10 before 5.18.1 — fixed in 5.18.1
How to fix
Upgrade to a fixed version: withastro astro 5.18.1. Check the vendor advisory for mitigations.
References
Get alerted when CVE-2026-33769 or the next vulnerability affects your stack