Portainer CE vulnerabilities

An authentication bypass vulnerability in Portainer CE through 2.44.0 allows authenticated low-privileged users to bypass Docker proxy authorization checks via non-canonical URL normalization, defeating all authorization middleware. The proxy endpoint fails to normalize request paths before applying access controls, allowing crafted requests to be interpreted differently by the proxy and the authorization layer.

The insecure default settings of Portainer CE grant regular (non-admin) users privileges that allow host filesystem access and host-level code execution. An authenticated non-administrative user with endpoint access can exploit these settings to read host files or obtain root equivalent access on the host.

A user enumeration vulnerability was found in Portainer CE 2.19.4. During the authentication process, a difference in response time allows a remote unauthenticated attacker to determine if a username is valid.