ldb before 1.1.24, as used in the AD LDAP server in Samba 4.x before 4.1.22, 4.2.x before 4.2.7, and 4.3.x before 4.3.3, mishandles string lengths, which allows remote attackers to obtain sensitive information from daemon heap memory by sending crafted packets and then reading (1) an error message or (2) a database value.
The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.