SSRF in Withastro @Astrojs/cloudflare

CVE-2026-41321

@astrojs/cloudflare is an SSR adapter for use with Cloudflare Workers targets. Prior to 13.1.10, the fetch() call for remote images in packages/integrations/cloudflare/src/utils/image-binding-transform.ts uses the default redirect: 'follow' behavior. This allows the Cloudflare Worker to follow HTTP redirects to arbitrary URLs, bypassing the isRemoteAllowed() domain allowlist check which only validates the initial URL. This vulnerabiity is caused by an incomplete fix for CVE-2025-58179. This vulnerability is fixed in 13.1.10.

Vulnerability class: SSRF (Server-Side Request Forgery)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 2.2 (Low). Vector: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:L.

EPSS exploit prediction

EPSS: 0.003 (22.2th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 22nd percentile — 22.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-41321: held from 0.002 to 0.003.

EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.001

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-41321?
CVE-2026-41321 is a low-severity vulnerability in Withastro @Astrojs/cloudflare, classified under Server-Side Request Forgery (SSRF). CVSS score: 2.2/10. Published 2026-04-24.
How severe is CVE-2026-41321?
Low severity. CVSS v3 base score is 2.2 out of 10.