The remote host is running a Telnet/SSH client containing multiple potential vulnerabilities.
The remote host is using a vulnerable version of PuTTY or of a PuTTY-based software (eg. PSCP or WinSCP). PuTTY is a Telnet/SSH client built for Linux and UNIX variants as well as Microsoft Windows operating systems. Reportedly PuTTY is affected by a buffer overflow (CVE-2013-4207) that could lead to remote code execution, a buffer underflow (CVE-2013-4206) that can corrupt the heap or cause a denial of service condition, and multiple information disclosure vulnerabilities due to its failure to properly clean the private keys typed by the user from memory during authentication.