Multiple buffer overflows in IBM Tivoli Storage Manager (TSM) before 5.2.9 and 5.3.x before 5.3.4 allow remote attackers to cause a denial of service (crash) and possibly execute arbitrary code via a long string in (1) the language field at logon that begins with a 0x18 byte, (2) two unspecified parameters to the SmExecuteWdsfSession function, and (3) the contact field in an open registration message.