The Netlogon server implementation in smbd in Samba 3.5.x and 3.6.x before 3.6.25, 4.0.x before 4.0.25, 4.1.x before 4.1.17, and 4.2.x before 4.2.0rc5 performs a free operation on an uninitialized stack pointer, which allows remote attackers to execute arbitrary code via crafted Netlogon packets that use the ServerPasswordSet RPC API, as demonstrated by packets reaching the _netr_ServerPasswordSet function in rpc_server/netlogon/srv_netlog_nt.c.

Samba 4.0.x before 4.0.24, 4.1.x before 4.1.16, and 4.2.x before 4.2rc4, when an Active Directory Domain Controller (AD DC) is configured, allows remote authenticated users to set the LDB userAccountControl UF_SERVER_TRUST_ACCOUNT bit, and consequently gain privileges, by leveraging delegation of authority for user-account or computer-account creation.

NetBIOS name services daemon (nmbd) in Samba 4.0.x before 4.0.21 and 4.1.x before 4.1.11 allows remote attackers to execute arbitrary code via unspecified vectors that modify heap memory, involving a sizeof operation on an incorrect variable in the unstrcpy macro in string_wrappers.h.

The push_ascii function in smbd in Samba 3.6.x before 3.6.24, 4.0.x before 4.0.19, and 4.1.x before 4.1.9 allows remote authenticated users to cause a denial of service (memory corruption and daemon crash) via an attempt to read a Unicode pathname without specifying use of Unicode, leading to a character-set conversion failure that triggers an invalid pointer dereference.

The sys_recvfrom function in nmbd in Samba 3.6.x before 3.6.24, 4.0.x before 4.0.19, and 4.1.x before 4.1.9 allows remote attackers to cause a denial of service (infinite loop and CPU consumption) via a malformed UDP packet.