Samba from version 4.0.0 and before versions 4.7.12, 4.8.7, 4.9.3 is vulnerable to a denial of service. During the processing of an LDAP search before Samba's AD DC returns the LDAP entries to the client, the entries are cached in a single memory object with a maximum size of 256MB. When this size is reached, the Samba process providing the LDAP service will follow the NULL pointer, terminating the process. There is no further vulnerability associated with this issue, merely a denial of service.
Samba from version 4.7.0 has a vulnerability that allows a user in a Samba AD domain to crash the KDC when Samba is built in the non-default MIT Kerberos configuration. With this advisory the Samba Team clarify that the MIT Kerberos build of the Samba AD DC is considered experimental. Therefore the Samba Team will not issue security patches for this configuration. Additionally, Samba 4.7.12, 4.8.7 and 4.9.3 have been issued as security releases to prevent building of the AD DC with MIT Kerberos unless --with-experimental-mit-ad-dc is specified to the configure command.
A heap-buffer overflow was found in the way samba clients processed extra long filename in a directory listing. A malicious samba server could use this flaw to cause arbitrary code execution on a samba client. Samba versions before 4.6.16, 4.7.9 and 4.8.4 are vulnerable.
A null pointer dereference flaw was found in the way samba checked database outputs from the LDB database layer. An authenticated attacker could use this flaw to crash a samba server in an Active Directory Domain Controller configuration. Samba versions before 4.7.9 and 4.8.4 are vulnerable.
The Samba Active Directory LDAP server was vulnerable to an information disclosure flaw because of missing access control checks. An authenticated attacker could use this flaw to extract confidential attribute values using LDAP search expressions. Samba versions before 4.6.16, 4.7.9 and 4.8.4 are vulnerable.
A flaw was found in the way samba before 4.7.9 and 4.8.4 allowed the use of weak NTLMv1 authentication even when NTLMv1 was explicitly disabled. A man-in-the-middle attacker could use this flaw to read the credential and other details passed between the samba server and client.
Unspecified vulnerability on HP NonStop Servers with software H06.x through H06.23.00 and J06.x through J06.12.00, when Samba is used, allows remote authenticated users to execute arbitrary code via unknown vectors.