08/04/03 DataSEC Advisory http://www.data-sec.com ------------------------------------------------------- Application: Hyperion FTP Server Web Site: http://www.mollensoft.com Versions: 3.0.0 Platform: Windows Bug: Buffer Overflow. Risk: Remote DOS and unauthorised remote access. --------------------- 1) Introduction 2) Bug 3) The Code 4) Fix =============== 1) Introduction =============== Hyperion FTP Server is a powerful, reliable FTP server for Windows95/98/NT/2000, and supports all basic FTP commands, and much more, such as passive mode. ====== 2) Bug ====== Buffer Overflow in the USER field. Any remote attacker can cause DOS and in some cases get unauthorised remote access to the server. when sending a string in the user field with more than 931 chars. =========== 3) The Code =========== telnet 21 A * 931 connection closed. -- server overflow will occur. ====== 4) Fix ====== Mollensoft have been informed about this issue and released a new version, however they did not gave it a new version number. Anyone who is using version installed before 5/4/03 is advised to download and install the new version.