CVE-2021-20277 log

Severity Medium
Remote Yes
Type Information disclosure
A security issue has been found in Samba before version 4.14.2. A string in an LDAP attribute that contains multiple consecutive leading spaces can lead to a memmove() of out of bounds memory in ldb_handler_fold(). ldb_handler_fold() is used by case insensitive strings - that is most string attributes - in Active Directory. As the search expression is normalised prior to matching any potential objects this in turn may crash the LDAP server process handling the request. It may be possible to leak the out of bounds memory by matching against it, but this is thought to be unlikely.
Group Package Affected Fixed Severity Status Ticket
AVG-1734 ldb 1:2.2.0-3 1:2.3.0-1 Medium Fixed
AVG-1732 samba 4.14.0-2 4.14.2-1 Medium Fixed

To disable the LDAP server set 'server services = -ldap' in the smb.conf and restart Samba. This will substantially reduce the utility of the AD DC.