MEDIUM (2)
Unencrypted Telnet Server
Plugin ID: 42263
Port: tcp/23
The remote host is running a Telnet server over an unencrypted
channel.
Using Telnet over an unencrypted channel is not recommended as logins,
passwords, and commands are transferred in cleartext. This allows a
remote, man-in-the-middle attacker to eavesdrop on a Telnet session to
obtain credentials or other sensitive information and to modify
traffic exchanged between a client and server.
SSH is preferred over Telnet since it protects credentials from
eavesdropping and can tunnel additional data streams such as an X11
session.
Javasolt megoldás
Disable the Telnet service and use SSH instead.
Network Time Protocol (NTP) Mode 6 Scanner
Plugin ID: 97861
Port: udp/123
The remote NTP server responds to mode 6 queries. Devices that respond
to these queries have the potential to be used in NTP amplification
attacks. An unauthenticated, remote attacker could potentially exploit
this, via a specially crafted mode 6 query, to cause a reflected
denial of service condition.
Javasolt megoldás
Restrict NTP mode 6 queries.
LOW (1)
ICMP Timestamp Request Remote Date Disclosure
The remote host answers to an ICMP timestamp request. This allows an
attacker to know the date that is set on the targeted machine, which
may assist an unauthenticated, remote attacker in defeating time-based
authentication protocols.
Timestamps returned from machines running Windows Vista / 7 / 2008 /
2008 R2 are deliberately incorrect, but usually within 1000 seconds of
the actual system time.
Javasolt megoldás
Filter out the ICMP timestamp requests (13), and the outgoing ICMP
timestamp replies (14).