CVE-2014-0244

La función sys_recvfrom en nmbd en Samba 3.6.x anterior a 3.6.24, 4.0.x anterior a 4.0.19 y 4.1.x anterior a 4.1.9 permite a atacantes remotos causar una denegación de servicio (bucle infinito y consumo de CPU) a través de un paquete UDP malformado.

A denial of service flaw was found in the way the sys_recvfile() function of nmbd, the NetBIOS message block daemon, processed non-blocking sockets. An attacker could send a specially crafted packet that, when processed, would cause nmbd to enter an infinite loop and consume an excessive amount of CPU time.

In Samba before 3.6.23, the SAMR server neglects to ensure that attempted password changes will update the bad password count, and does not set the lockout flags. This would allow a user unlimited attempts against the password by simply calling ChangePasswordUser2 repeatedly. This is available without any other authentication. Information leak vulnerability in the VFS code, allowing an authenticated user to retrieve eight bytes of uninitialized memory when shadow copy is enabled. Samba versions before 3.6.24, 4.0.19, and 4.1.9 are vulnerable to a denial of service on the nmbd NetBIOS name services daemon. A malformed packet can cause the nmbd server to loop the CPU and prevent any further NetBIOS ame service. Samba versions before 3.6.24, 4.0.19, and 4.1.9 are affected by a denial of service crash involving overwriting memory on an authenticated connection to the smbd file server. An uninitialized pointer use flaw was found in the Samba daemon (smbd). A malicious Samba client could send specially crafted netlogon packets that, when processed by smbd, could potentially lead to arbitrary code execution with the privileges of the user running smbd (by default, the root user).