CVE-2026-44848: Portainer: Missing authorization on Docker plugin endpoints allows host RCE

Synopsis

Missing authorization on Docker plugin management endpoints in Portainer Community Edition allows any authenticated standard user with endpoint access to install and enable Docker plugins directly against the underlying Docker daemon. The vulnerability is reachable over the network and requires only a low-privilege Portainer account with endpoint-level access granted via Portainer RBAC. Successful exploitation gives an attacker the ability to install arbitrary Docker plugins, which run as root on the host and enable full host-level remote code execution, data access, and service disruption. No fix versions have been published yet; HarborGuard is tracking the advisory and will make a patched-image rebuild available the moment upstream ships a release.

HarborGuard Coverage

Exploit Conditions

• Network reachabilityRequired

  The attacker must reach the Portainer web service over the network; the vulnerable plugin management endpoints are exposed via Portainer's HTTP API.

• AuthenticationRequired

  A low-privilege Portainer account is sufficient; any Standard User role or any role with endpoint-level access granted via Portainer RBAC can trigger the vulnerable endpoints.

• Victim interactionNot required

  No victim interaction is needed; the attacker calls the plugin management API directly without any user action required on the target side.

• Attack complexityDetail

  Attack complexity is low; the exploit is reliable and condition-free, requiring no race conditions, memory layout dependencies, or special environmental factors.

Blast Radius

• Installs and enables arbitrary Docker plugins running as root on the host, giving the attacker full host-level code execution.
• Reads any data accessible on the Docker host, including secrets, credentials, and filesystem contents from all co-located containers.
• Modifies or destroys container workloads, host filesystem contents, and persisted data on the underlying Docker daemon.
• Disrupts or terminates any running containers and services on the affected Docker host, causing availability loss across all workloads on that host.