CVE-2026-27589: Caddyserver Caddy

Medium severity, CVSS 6.5. EPSS: 0.2% chance of exploitation in the next 30 days.

Caddy is an extensible server platform that uses TLS by default. Prior to version 2.11.1, the local caddy admin API (default listen `127.0.0.1:2019`) exposes a state-changing `POST /load` endpoint that replaces the entire running configuration. When origin enforcement is not enabled (`enforce_origin` not configured), the admin endpoint accepts cross-origin requests (e.g., from attacker-controlled web content in a victim browser) and applies an attacker-supplied JSON config. This can change the admin listener settings and alter HTTP server behavior without user intent. Version 2.11.1 contains a fix for the issue.

Affected products

• Caddyserver Caddy: before 2.11.1 (fixed in 2.11.1)

Published 2026-02-24. Last modified 2026-06-17.