OpenSSH timing attacks

It's possible to check user's validity by measuring response time...

CVE-2003-0305

The Service Assurance Agent SAA in Cisco IOS 12.0 through 12.2, aka Response Time Reporter RTR, allows remote attackers to cause a denial of service crash via malformed RTR packets to port 1967...

Linux Kernel 2.2.x/2.4.x - I/O System Call File Existence

/ source: https://www.securityfocus.com/bid/7279/info A weakness has been discovered on various systems that may result in an attacker gaining information pertaining to the existence of inaccessible files. The problem lies in the return times when attempting to access existent and non-existent...