In SolarWinds Serv-U before 15.2.2 Hotfix 1, there is a directory containing user profile files (that include users' password hashes) that is world readable and writable. An unprivileged Windows user (having access to the server's filesystem) can add an FTP user by copying a valid profile file to this directory. For example, if this profile sets up a user with a C:\ home directory, then the attacker obtains access to read or replace arbitrary files with LocalSystem privileges.

The Collector Service in SolarWinds Orion Platform before 2020.2.4 uses MSMQ (Microsoft Message Queue) and doesn't set permissions on its private queues. As a result, remote unauthenticated clients can send messages to TCP port 1801 that the Collector Service will process. Additionally, upon processing of such messages, the service deserializes them in insecure manner, allowing remote arbitrary code execution as LocalSystem.