In Pivotal Spring-LDAP versions 1.3.0 - 2.3.1, when connected to some LDAP servers, when no additional attributes are bound, and when using LDAP BindAuthenticator with org.springframework.ldap.core.support.DefaultTlsDirContextAuthenticationStrategy as the authentication strategy, and setting userSearch, authentication is allowed with an arbitrary password when the username is correct. This occurs because some LDAP vendors require an explicit operation for the LDAP bind to take effect.
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.