The NTLMSSP authentication implementation in Samba 3.x and 4.x before 4.2.11, 4.3.x before 4.3.8, and 4.4.x before 4.4.2 allows man-in-the-middle attackers to perform protocol-downgrade attacks by modifying the client-server data stream to remove application-layer flags or encryption settings, as demonstrated by clearing the NTLMSSP_NEGOTIATE_SEAL or NTLMSSP_NEGOTIATE_SIGN option to disrupt LDAP security.
Samba 3.x and 4.x before 4.2.11, 4.3.x before 4.3.8, and 4.4.x before 4.4.2 does not properly implement the DCE-RPC layer, which allows remote attackers to perform protocol-downgrade attacks, cause a denial of service (application crash or CPU consumption), or possibly execute arbitrary code on a client system via unspecified vectors.
The MS-SAMR and MS-LSAD protocol implementations in Samba 3.x and 4.x before 4.2.11, 4.3.x before 4.3.8, and 4.4.x before 4.4.2 mishandle DCERPC connections, which allows man-in-the-middle attackers to perform protocol-downgrade attacks and impersonate users by modifying the client-server data stream, aka "BADLOCK."
The internal DNS server in Samba 4.x before 4.1.23, 4.2.x before 4.2.9, 4.3.x before 4.3.6, and 4.4.x before 4.4.0rc4, when an AD DC is configured, allows remote authenticated users to cause a denial of service (out-of-bounds read) or possibly obtain sensitive information from process memory by uploading a crafted DNS TXT record.
The SMB1 implementation in smbd in Samba 3.x and 4.x before 4.1.23, 4.2.x before 4.2.9, 4.3.x before 4.3.6, and 4.4.x before 4.4.0rc4 allows remote authenticated users to modify arbitrary ACLs by using a UNIX SMB1 call to create a symlink, and then using a non-UNIX SMB1 call to write to the ACL content.
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.