Due to incorrect access control in Neo4j Enterprise Database Server 3.4.x before 3.4.9, the setting of LDAP for authentication with STARTTLS, and System Account for authorization, allows an attacker to log into the server by sending any valid username with an arbitrary password.
CWE-287 - Improper Authentication
Improper (or broken) authentication attacks are widespread, and have accounted for many of the worst data breaches in recent years. Improper authentication attacks are a class of vulnerabilities where an attacker impersonates a legitimate user by exploiting weaknesses in either session management or credential management to gain access to the user’s account. This can result in disclosure of sensitive information, and can lead to system compromise, theft, identity theft, and fraud.