RCE in Fuomag9 Caddy-Proxy-Manager

CVE-2026-54907

Caddy Proxy Manager is a web interface for managing Caddy Server reverse proxies and certificates. Prior to 1.5.1, Caddy Proxy Manager enables email and password self-registration by default at /api/auth/sign-up/email, allowing an unauthenticated remote actor to create an active account with the user role without administrator approval. The user role cannot view or modify proxy data, so the direct impact is limited to unauthorized creation of low-privilege accounts. The fixed configuration in src/lib/config.ts and src/lib/auth-server.ts requires AUTH_ALLOW_SELF_REGISTRATION=true before the authentication library's disableSignUp control permits sign-up. This issue is fixed in version 1.5.1.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N.

EPSS exploit prediction

EPSS: 0.003 (21.6th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 22nd percentile — 21.6% 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-2026-54907: held from 0.003 to 0.003.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-54907?
CVE-2026-54907 is a medium-severity vulnerability in Fuomag9 Caddy-Proxy-Manager, classified under Initialization of a Resource with an Insecure Default. CVSS score: 5.3/10. Published 2026-09-17.
How severe is CVE-2026-54907?
Medium severity. CVSS v3 base score is 5.3 out of 10.