Rkhunter

This is the warning: Checking for hidden files and directories [ Warning ]

In fact this is what Terminal turned up:

 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 [ OK ]
    /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/ed [ OK ]
    /bin/egrep [ OK ]
    /bin/fgrep [ OK ]
    /bin/grep [ OK ]
    /bin/ip [ OK ]
    /bin/kill [ 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/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/md5sum [ OK ]
    /usr/bin/newgrp [ OK ]
    /usr/bin/passwd [ OK ]
    /usr/bin/perl [ OK ]
    /usr/bin/pstree [ OK ]
    /usr/bin/rkhunter [ OK ]
    /usr/bin/runcon [ OK ]
    /usr/bin/sha1sum [ OK ]
    /usr/bin/size [ OK ]
    /usr/bin/slocate [ OK ]
    /usr/bin/sort [ OK ]
    /usr/bin/stat [ OK ]
    /usr/bin/strace [ OK ]
    /usr/bin/strings [ OK ]
    /usr/bin/sudo [ 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/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 ]
    /sbin/syslogd [ 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/tcpd [ OK ]
    /usr/sbin/useradd [ OK ]
    /usr/sbin/userdel [ OK ]
    /usr/sbin/usermod [ OK ]
    /usr/sbin/vipw [ OK ]

[Press <ENTER> to continue]

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 ]
    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 ]
    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 ]
    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 inetd services [ OK ]

  Performing Linux specific checks
    Checking kernel module commands [ OK ]
    Checking kernel module names [ OK ]

[Press <ENTER> to continue]

Checking the network...

  Performing check for backdoor ports
    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 14856 [ Not found ]
    Checking for TCP port 47107 [ Not found ]
    Checking for TCP port 60922 [ Not found ]

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

[Press <ENTER> to continue]

Checking the local host...

  Performing system boot checks
    Checking for local host name [ Found ]
    Checking for local startup files [ Found ]
    Checking local startup files for malware [ None 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 [ None found ]
    Checking for group file changes [ None found ]
    Checking root account shell history files [ None found ]

  Performing system configuration file checks
    Checking for SSH configuration file [ Not found ]
    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 ]

[Press <ENTER> to continue]

Checking application versions...

    Checking version of Exim MTA [ OK ]
    Checking version of GnuPG [ OK ]
    Checking version of OpenSSL [ OK ]

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

File properties checks...
    Files checked: 122
    Suspect files: 0

Rootkit checks...
    Rootkits checked : 109
    Possible rootkits: 0

Applications checks...
    Applications checked: 3
    Suspect applications: 0

The system checks took: 1 minute and 1 second

All results have been written to the logfile (/var/log/rkhunter.log)

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

This is the bit I need to check and I can't open the file: Please check the log file (/var/log/rkhunter.log

Please open a Terminal and type:
with Kubuntu
sudo kate /var/log/rkhunter.log
or with Gnome
sudo kate /var/log/rkhunter.log

HTH

Please open a Terminal and type:
with Kubuntu
sudo kate /var/log/rkhunter.log
or with Gnome
sudo kate /var/log/rkhunter.log

I'm using Ubuntu 7.10 with the Gnome Desktop.

Tried both commands without success. Can't open: /var/log/rkhunter.log

sorry, with Gnome
sudo gedit /var/log/rkhunter.log

Thanks Marcoba!

Used: sudo gedit /var/log/rkhunter.log and that worked.

This is what it revealed:

[00:46:03] Checking for hidden files and directories [ Warning ]
[00:46:03] Warning: Hidden directory found: /etc/.java
[00:46:03] Warning: Hidden directory found: /dev/.static
[00:46:03] Warning: Hidden directory found: /dev/.udev
[00:46:03] Warning: Hidden directory found: /dev/.initramfs

I don't think it's anything to worry about but I'd like one of you Linux wizards to confirm this.

If it's an FP as I suspect is there a command that will whitelist it?

Marcobra: TY for the excellent support. Have done as you suggested and installed chkrootkit. It found nothing; I'm in the clear and this was confirmed by someone who is very knowledgeable in all manner of things concerning Linux.

Thanks marcobra, that solved my question.