[ SOURCE: http://www.secureroot.com/security/advisories/9678231071.html ] GoodTech's FTP Server vulnerable to a DoS (RNTO) ---------------------------------------------------------------------------- SUMMARY GoodTech's FTP Server contains a security hole that allows a remote user to launch a Denial of Service attack against the product just by sending a simple FTP command. DETAILS Vulnerable systems: FTP Server dated before 26/08/2000 (3.0.1, and 3.0) Immune systems: FTP Server dated 26/08/2000 and later By issuing a RNTO command to GoodTech's FTP Server it is possible to cause it to hang, effectively blocking the listening socket thread. If done enough times this can be used to exhaust all available sockets of the server, effectively causing a Denial of Service attack. Patch: The immune version can be downloaded from: http://www.goodtechsys.com/predownload.asp ADDITIONAL INFORMATION The security hole was discovered by SecuriTeam (expert@securiteam.com). ==================== DISCLAIMER: The information in this bulletin is provided "AS IS" without warranty of any kind. In no event shall we be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages. ==================== -- Aviram Jenik Beyond Security Ltd. http://www.BeyondSecurity.com http://www.SecuriTeam.com