All versions of the package github.com/greenpau/caddy-security are vulnerable to Improper Restriction of Excessive Authentication Attempts via the two-factor authentication (2FA). Although the application blocks the user after several failed attempts to provide 2FA codes, attackers can bypass this blocking mechanism by automating the application’s full multistep 2FA process.

All versions of the package github.com/greenpau/caddy-security are vulnerable to Server-side Request Forgery (SSRF) via X-Forwarded-Host header manipulation. An attacker can expose sensitive information, interact with internal services, or exploit other vulnerabilities within the network by exploiting this vulnerability.

All versions of the package github.com/greenpau/caddy-security are vulnerable to Cross-site Scripting (XSS) via the Referer header, due to improper input sanitization. Although the Referer header is sanitized by escaping some characters that can allow XSS (e.g., [&], [<], [>], ["], [']), it does not account for the attack based on the JavaScript URL scheme (e.g., javascript:alert(document.domain)// payload). Exploiting this vulnerability may not be trivial, but it could lead to the execution of malicious scripts in the context of the target user’s browser, compromising user sessions.

All versions of the package github.com/greenpau/caddy-security are vulnerable to Insufficient Session Expiration due to improper user session invalidation upon clicking the "Sign Out" button. User sessions remain valid even after requests are sent to /logout and /oauth2/google/logout. Attackers who gain access to an active but supposedly logged-out session can perform unauthorized actions on behalf of the user.

The caddy-security plugin 1.1.20 for Caddy allows reflected XSS via a GET request to a URL that contains an XSS payload and begins with either a /admin or /settings/mfa/delete/ substring.