The LDAPLoginModule implementation in the Java Authentication and Authorization Service (JAAS) in Apache ActiveMQ 5.x before 5.10.1 allows remote attackers to bypass authentication by logging in with an empty password and valid username, which triggers an unauthenticated bind. NOTE: this identifier has been SPLIT per ADT2 due to different vulnerability types. See CVE-2015-6524 for the use of wildcard operators in usernames.
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.