how to understand watchdog log and fix the problems?

Question

In My plesk application, I started a watchdog scan and I got this report but I'm unable to understand it. Could you please help me understand the [ No update ] and [ Warning ] entries and fix them? How can I find the tree Suspect applications mentioned at the end?

My system is Debian 6.0.7, and Plesk 11.0.9:

[ Rootkit Hunter version 1.3.4 ]

Checking rkhunter data files...
Checking file mirrors.dat                                  [ No update ]
Checking file programs_bad.dat                             [ Updated ]
Checking file backdoorports.dat                            [ Updated ]
Checking file suspscan.dat                                 [ Updated ]
Checking file i18n/cn                                      [ No update ]
Checking file i18n/de                                      [ Updated ]
Checking file i18n/en                                      [ No update ]
Checking file i18n/zh                                      [ No update ]
Checking file i18n/zh.utf8                                 [ No update ]
[ Rootkit Hunter version 1.3.4 ]
File created: searched for 153 files, found 124

Checking system commands...

Performing 'strings' command checks
Checking 'strings' command                               [ OK ]

Performing 'shared libraries' checks
Checking for preloading variables                        [ None found ]
Checking for preload file                                [ Not found ]
Checking LD_LIBRARY_PATH variable                        [ Not found ]

Performing file properties checks
Checking for prerequisites                               [ Warning ]
/bin/bash                                                [ OK ]
/bin/cat                                                 [ OK ]
/bin/chmod                                               [ OK ]
/bin/chown                                               [ OK ]
/bin/cp                                                  [ OK ]
/bin/date                                                [ OK ]
/bin/df                                                  [ OK ]
/bin/dmesg                                               [ OK ]
/bin/echo                                                [ OK ]
/bin/egrep                                               [ OK ]
/bin/fgrep                                               [ OK ]
/bin/fuser                                               [ OK ]
/bin/grep                                                [ OK ]
/bin/ip                                                  [ OK ]
/bin/kill                                                [ OK ]
/bin/less                                                [ OK ]
/bin/login                                               [ OK ]
/bin/ls                                                  [ OK ]
/bin/lsmod                                               [ OK ]
/bin/mktemp                                              [ OK ]
/bin/more                                                [ OK ]
/bin/mount                                               [ OK ]
/bin/mv                                                  [ OK ]
/bin/netstat                                             [ OK ]
/bin/ps                                                  [ OK ]
/bin/pwd                                                 [ OK ]
/bin/readlink                                            [ OK ]
/bin/sed                                                 [ OK ]
/bin/sh                                                  [ OK ]
/bin/su                                                  [ OK ]
/bin/touch                                               [ OK ]
/bin/uname                                               [ OK ]
/bin/which                                               [ OK ]
/bin/dash                                                [ OK ]
/usr/bin/awk                                             [ OK ]
/usr/bin/basename                                        [ OK ]
/usr/bin/chattr                                          [ OK ]
/usr/bin/curl                                            [ OK ]
/usr/bin/cut                                             [ OK ]
/usr/bin/diff                                            [ OK ]
/usr/bin/dirname                                         [ OK ]
/usr/bin/dpkg                                            [ OK ]
/usr/bin/dpkg-query                                      [ OK ]
/usr/bin/du                                              [ OK ]
/usr/bin/env                                             [ OK ]
/usr/bin/file                                            [ OK ]
/usr/bin/find                                            [ OK ]
/usr/bin/GET                                             [ OK ]
/usr/bin/groups                                          [ OK ]
/usr/bin/head                                            [ OK ]
/usr/bin/id                                              [ OK ]
/usr/bin/killall                                         [ OK ]
/usr/bin/last                                            [ OK ]
/usr/bin/lastlog                                         [ OK ]
/usr/bin/ldd                                             [ OK ]
/usr/bin/less                                            [ OK ]
/usr/bin/locate                                          [ OK ]
/usr/bin/logger                                          [ OK ]
/usr/bin/lsattr                                          [ OK ]
/usr/bin/lsof                                            [ OK ]
/usr/bin/mail                                            [ OK ]
/usr/bin/md5sum                                          [ OK ]
/usr/bin/mlocate                                         [ OK ]
/usr/bin/newgrp                                          [ OK ]
/usr/bin/passwd                                          [ OK ]
/usr/bin/perl                                            [ OK ]
/usr/bin/pstree                                          [ OK ]
/usr/bin/runcon                                          [ OK ]
/usr/bin/sha1sum                                         [ OK ]
/usr/bin/size                                            [ OK ]
/usr/bin/sort                                            [ OK ]
/usr/bin/stat                                            [ OK ]
/usr/bin/strings                                         [ OK ]
/usr/bin/tail                                            [ OK ]
/usr/bin/test                                            [ OK ]
/usr/bin/top                                             [ OK ]
/usr/bin/touch                                           [ OK ]
/usr/bin/tr                                              [ OK ]
/usr/bin/uniq                                            [ OK ]
/usr/bin/users                                           [ OK ]
/usr/bin/vmstat                                          [ OK ]
/usr/bin/w                                               [ OK ]
/usr/bin/watch                                           [ OK ]
/usr/bin/wc                                              [ OK ]
/usr/bin/wget                                            [ OK ]
/usr/bin/whatis                                          [ OK ]
/usr/bin/whereis                                         [ OK ]
/usr/bin/which                                           [ OK ]
/usr/bin/who                                             [ OK ]
/usr/bin/whoami                                          [ OK ]
/usr/bin/gawk                                            [ OK ]
/usr/bin/lwp-request                                     [ OK ]
/usr/bin/bsd-mailx                                       [ OK ]
/usr/bin/w.procps                                        [ OK ]
/sbin/depmod                                             [ OK ]
/sbin/ifconfig                                           [ OK ]
/sbin/ifdown                                             [ OK ]
/sbin/ifup                                               [ OK ]
/sbin/init                                               [ OK ]
/sbin/insmod                                             [ OK ]
/sbin/ip                                                 [ OK ]
/sbin/lsmod                                              [ OK ]
/sbin/modinfo                                            [ OK ]
/sbin/modprobe                                           [ OK ]
/sbin/rmmod                                              [ OK ]
/sbin/runlevel                                           [ OK ]
/sbin/sulogin                                            [ OK ]
/sbin/sysctl                                             [ OK ]
/usr/sbin/adduser                                        [ OK ]
/usr/sbin/chroot                                         [ OK ]
/usr/sbin/cron                                           [ OK ]
/usr/sbin/groupadd                                       [ OK ]
/usr/sbin/groupdel                                       [ OK ]
/usr/sbin/groupmod                                       [ OK ]
/usr/sbin/grpck                                          [ OK ]
/usr/sbin/nologin                                        [ OK ]
/usr/sbin/pwck                                           [ OK ]
/usr/sbin/rsyslogd                                       [ OK ]
/usr/sbin/tcpd                                           [ OK ]
/usr/sbin/useradd                                        [ OK ]
/usr/sbin/userdel                                        [ OK ]
/usr/sbin/usermod                                        [ OK ]
/usr/sbin/vipw                                           [ OK ]
/usr/sbin/xinetd                                         [ OK ]

Checking for rootkits...

 Performing check of known rootkit files and directories
55808 Trojan - Variant A                                 [ Not found ]
ADM Worm                                                 [ Not found ]
AjaKit Rootkit                                           [ Not found ]
aPa Kit                                                  [ Not found ]
Apache Worm                                              [ Not found ]
Ambient (ark) Rootkit                                    [ Not found ]
Balaur Rootkit                                           [ Not found ]
BeastKit Rootkit                                         [ Not found ]
beX2 Rootkit                                             [ Not found ]
BOBKit Rootkit                                           [ Not found ]
CiNIK Worm (Slapper.B variant)                           [ Not found ]
Danny-Boy's Abuse Kit                                    [ Not found ]
Devil RootKit                                            [ Not found ]
Dica-Kit Rootkit                                         [ Not found ]
Dreams Rootkit                                           [ Not found ]
Duarawkz Rootkit                                         [ Not found ]
Enye LKM                                                 [ Not found ]
Flea Linux Rootkit                                       [ Not found ]
FreeBSD Rootkit                                          [ Not found ]
Fuck`it Rootkit                                          [ Not found ]
GasKit Rootkit                                           [ Not found ]
Heroin LKM                                               [ Not found ]
HjC Kit                                                  [ Not found ]
ignoKit Rootkit                                          [ Not found ]
ImperalsS-FBRK Rootkit                                   [ Not found ]
IntoXonia-NG Rootkit                                     [ Not found ]
Irix Rootkit                                             [ Not found ]
Kitko Rootkit                                            [ Not found ]
Knark Rootkit                                            [ Not found ]
Li0n Worm                                                [ Not found ]
Lockit / LJK2 Rootkit                                    [ Not found ]
Mood-NT Rootkit                                          [ Not found ]
MRK Rootkit                                              [ Not found ]
Ni0 Rootkit                                              [ Not found ]
Ohhara Rootkit                                           [ Not found ]
Optic Kit (Tux) Worm                                     [ Not found ]
Oz Rootkit                                               [ Not found ]
Phalanx Rootkit                                          [ Not found ]
Phalanx Rootkit (strings)                                [ Not found ]
Phalanx2 Rootkit                                         [ Not found ]
Phalanx2 Rootkit (extended tests)                        [ Not found ]
Portacelo Rootkit                                        [ Not found ]
R3dstorm Toolkit                                         [ Not found ]
RH-Sharpe's Rootkit                                      [ Not found ]
RSHA's Rootkit                                           [ Not found ]
Scalper Worm                                             [ Not found ]
Sebek LKM                                                [ Not found ]
Shutdown Rootkit                                         [ Not found ]
SHV4 Rootkit                                             [ Not found ]
SHV5 Rootkit                                             [ Not found ]
Sin Rootkit                                              [ Not found ]
Slapper Worm                                             [ Not found ]
Sneakin Rootkit                                          [ Not found ]
Suckit Rootkit                                           [ Not found ]
SunOS Rootkit                                            [ Not found ]
SunOS / NSDAP Rootkit                                    [ Not found ]
Superkit Rootkit                                         [ Not found ]
TBD (Telnet BackDoor)                                    [ Not found ]
TeLeKiT Rootkit                                          [ Not found ]
T0rn Rootkit                                             [ Not found ]
Trojanit Kit                                             [ Not found ]
Tuxtendo Rootkit                                         [ Not found ]
URK Rootkit                                              [ Not found ]
Vampire Rootkit                                          [ Not found ]
VcKit Rootkit                                            [ Not found ]
Volc Rootkit                                             [ Not found ]
X-Org SunOS Rootkit                                      [ Not found ]
zaRwT.KiT Rootkit                                        [ Not found ]

 Performing additional rootkit checks
Suckit Rookit additional checks                          [ OK ]
Checking for possible rootkit files and directories      [ None found ]
Checking for possible rootkit strings                    [ None found ]

 Performing malware checks
Checking running processes for suspicious files          [ None found ]
Checking for login backdoors                             [ None found ]
Checking for suspicious directories                      [ None found ]
Checking for sniffer log files                           [ None found ]

 Performing trojan specific checks
Checking for enabled xinetd services                     [ Warning ]
Checking for Apache backdoor                             [ Not found ]

 Performing Linux specific checks
Checking loaded kernel modules                           [ OK ]
Checking kernel module names                             [ OK ]


  Checking the network...

 Performing check for backdoor ports
Checking for TCP port 1524                               [ Not found ]
Checking for TCP port 1984                               [ Not found ]
Checking for UDP port 2001                               [ Not found ]
Checking for TCP port 2006                               [ Not found ]
Checking for TCP port 2128                               [ Not found ]
Checking for TCP port 6666                               [ Not found ]
Checking for TCP port 6667                               [ Not found ]
Checking for TCP port 6668                               [ Not found ]
Checking for TCP port 6669                               [ Not found ]
Checking for TCP port 7000                               [ Not found ]
Checking for TCP port 13000                              [ Not found ]
Checking for TCP port 14856                              [ Not found ]
Checking for TCP port 25000                              [ Not found ]
Checking for TCP port 29812                              [ Not found ]
Checking for TCP port 31337                              [ Not found ]
Checking for TCP port 32982                              [ Not found ]
Checking for TCP port 33369                              [ Not found ]
Checking for TCP port 47107                              [ Not found ]
Checking for TCP port 47018                              [ Not found ]
Checking for TCP port 60922                              [ Not found ]
Checking for TCP port 62883                              [ Not found ]
Checking for TCP port 65535                              [ Not found ]

 Performing checks on the network interfaces
Checking for promiscuous interfaces                      [ None found ]

 Checking the local host...

 Performing system boot checks
Checking for local host name                             [ Found ]
Checking for system startup files                        [ Found ]
Checking system startup files for malware                [ None found ]

  Performing group and account checks
Checking for passwd file                                 [ Found ]
Checking for root equivalent (UID 0) accounts            [ None found ]
Checking for passwordless accounts                       [ None found ]
Checking for passwd file changes                         [ Warning ]
Checking for group file changes                          [ Warning ]
Checking root account shell history files                [ OK ]

 Performing system configuration file checks
Checking for SSH configuration file                      [ Found ]
Checking if SSH root access is allowed                   [ Warning ]
Checking if SSH protocol v1 is allowed                   [ Not allowed ]
Checking for running syslog daemon                       [ Found ]
Checking for syslog configuration file                   [ Found ]
Checking if syslog remote logging is allowed             [ Not allowed ]

  Performing filesystem checks
Checking /dev for suspicious file types                  [ None found ]
Checking for hidden files and directories                [ Warning ]


     Checking application versions...

Checking version of GnuPG                                [ Warning ]
Checking version of Bind DNS                             [ OK ]
Checking version of OpenSSL                              [ Warning ]
Checking version of PHP                                  [ OK ]
Checking version of Procmail MTA                         [ OK ]
Checking version of ProFTPd                              [ Skipped ]
Checking version of OpenSSH                              [ Warning ]


 System checks summary
  =====================

  File properties checks...
Required commands check failed
Files checked: 124
Suspect files: 0

   Rootkit checks...
Rootkits checked : 112
Possible rootkits: 0

  Applications checks...
Applications checked: 7
Suspect applications: 3

  The system checks took: 36 seconds



      One or more warnings have been found while checking the system.
      Please check the log file (/var/log/***.log)

Answer 1

Search for more information about rkhunter. Read the manual etc. Helps you understand how it works. Plesk calls this system watchdog but in fact it is rkhunter.

Rkhunter scans files and saves/remembers how they 'look'. So if a file changes rkhunter will show a warning. If this warning is correct, because of an update or an intended change you will have to tell rkhunter the files have been changed and can be remembered in this state. Therefore you run the command rkhunter --propupd or something like: /opt/psa/admin/bin/modules/watchdog/rkhunter --propupd. Pay attention though! Only give this command when you are pretty sure your system is clean.

A good common practice is to run rkhunter --propupd on a new clean install. And run rkhunter -c --rwo (report warnings only) before an update and check for warnings. Run the update e.g. apt-get upgrade and afterwards run rkhunter --propupd again. Of course this takes time and effort!

The three version warnings probably don't really matter. Debian is not a distribution that quickly upgrades/updates, because they review extensively and therefore are really stable and secure as well. So you will often find versions to be outdated on a Debian system according to rkhunter.