[SOLVED] chkrootkit and rkhunter output interpretation

[Lamios]

Hey,

I checked my system with chkrootkit and rkhunter, but I do not really know what the output means. Searching for the topic and output pieces in the internet did not really help me.

I am running Debian Stretch with KDE and I have installed Sophos. I am using this system for about nearly 1 year, but installed chkrootkit and rkhunter recently.

The output from chkrootkit gave me the following:

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~# chkrootkit
ROOTDIR is `/'
Checking `amd'...                                           not found
Checking `basename'...                                      not infected
Checking `biff'...                                          not found
Checking `chfn'...                                          not infected
Checking `chsh'...                                          not infected
Checking `cron'...                                          not infected
Checking `crontab'...                                       not infected
Checking `date'...                                          not infected
Checking `du'...                                            not infected
Checking `dirname'...                                       not infected
Checking `echo'...                                          not infected
Checking `egrep'...                                         not infected
Checking `env'...                                           not infected
Checking `find'...                                          not infected
Checking `fingerd'...                                       not found
Checking `gpm'...                                           not found
Checking `grep'...                                          not infected
Checking `hdparm'...                                        not infected
Checking `su'...                                            not infected
Checking `ifconfig'...                                      not infected
Checking `inetd'...                                         not infected
Checking `inetdconf'...                                     not found
Checking `identd'...                                        not found
Checking `init'...                                          not infected
Checking `killall'...                                       not infected
Checking `ldsopreload'...                                   not infected
Checking `login'...                                         not infected
Checking `ls'...                                            not infected
Checking `lsof'...                                          not infected
Checking `mail'...                                          not infected
Checking `mingetty'...                                      not found
Checking `netstat'...                                       not infected
Checking `named'...                                         not found
Checking `passwd'...                                        not infected
Checking `pidof'...                                         not infected
Checking `pop2'...                                          not found
Checking `pop3'...                                          not found
Checking `ps'...                                            not infected
Checking `pstree'...                                        not infected
Checking `rpcinfo'...                                       not found
Checking `rlogind'...                                       not found
Checking `rshd'...                                          not found
Checking `slogin'...                                        not infected
Checking `sendmail'...                                      not infected
Checking `sshd'...                                          not found
Checking `syslogd'...                                       not tested
Checking `tar'...                                           not infected
Checking `tcpd'...                                          not infected
Checking `tcpdump'...                                       not infected
Checking `top'...                                           not infected
Checking `telnetd'...                                       not found
Checking `timed'...                                         not found
Checking `traceroute'...                                    not infected
Checking `vdir'...                                          not infected
Checking `w'...                                             not infected
Checking `write'...                                         not infected
Checking `aliens'...                                        no suspect files
Searching for sniffer's logs, it may take a while...        nothing found
Searching for rootkit HiDrootkit's default files...         nothing found
Searching for rootkit t0rn's default files...               nothing found
Searching for t0rn's v8 defaults...                         nothing found
Searching for rootkit Lion's default files...               nothing found
Searching for rootkit RSHA's default files...               nothing found
Searching for rootkit RH-Sharpe's default files...          nothing found
Searching for Ambient's rootkit (ark) default files and dirs... nothing found
Searching for suspicious files and dirs, it may take a while... The following suspicious files and directories were found:  
/usr/lib/jvm/.java-1.8.0-openjdk-amd64.jinfo /usr/lib/python3/dist-packages/PyQt5/uic/widget-plugins/.noinit

Searching for LPD Worm files and dirs...                    nothing found
Searching for Ramen Worm files and dirs...                  nothing found
Searching for Maniac files and dirs...                      nothing found
Searching for RK17 files and dirs...                        nothing found
Searching for Ducoci rootkit...                             nothing found
Searching for Adore Worm...                                 nothing found
Searching for ShitC Worm...                                 nothing found
Searching for Omega Worm...                                 nothing found
Searching for Sadmind/IIS Worm...                           nothing found
Searching for MonKit...                                     nothing found
Searching for Showtee...                                    nothing found
Searching for OpticKit...                                   nothing found
Searching for T.R.K...                                      nothing found
Searching for Mithra...                                     nothing found
Searching for LOC rootkit...                                nothing found
Searching for Romanian rootkit...                           nothing found
Searching for Suckit rootkit...                             nothing found
Searching for Volc rootkit...                               nothing found
Searching for Gold2 rootkit...                              nothing found
Searching for TC2 Worm default files and dirs...            nothing found
Searching for Anonoying rootkit default files and dirs...   nothing found
Searching for ZK rootkit default files and dirs...          nothing found
Searching for ShKit rootkit default files and dirs...       nothing found
Searching for AjaKit rootkit default files and dirs...      nothing found
Searching for zaRwT rootkit default files and dirs...       nothing found
Searching for Madalin rootkit default files...              nothing found
Searching for Fu rootkit default files...                   nothing found
Searching for ESRK rootkit default files...                 nothing found
Searching for rootedoor...                                  nothing found
Searching for ENYELKM rootkit default files...              nothing found
Searching for common ssh-scanners default files...          nothing found
Searching for Linux/Ebury - Operation Windigo ssh...        nothing found
Searching for 64-bit Linux Rootkit ...                      nothing found
Searching for 64-bit Linux Rootkit modules...               nothing found
Searching for suspect PHP files...                          nothing found
Searching for anomalies in shell history files...           nothing found
Checking `asp'...                                           not infected
Checking `bindshell'...                                     not infected
Checking `lkm'...                                           find: ‘/proc/4359/task/4359/net’: Invalid argument
find: ‘/proc/4359/net’: Invalid argument
chkproc: nothing detected
chkdirs: nothing detected
Checking `rexedcs'...                                       not found
Checking `sniffer'...                                       lo: not promisc and no packet sniffer sockets
wlp2s0: PACKET SNIFFER(/sbin/wpa_supplicant[736], /sbin/wpa_supplicant[736], /sbin/dhclient[8907])
Checking `w55808'...                                        not infected
Checking `wted'...                                          chkwtmp: nothing deleted
Checking `scalper'...                                       not infected
Checking `slapper'...                                       not infected
Checking `z2'...                                            user lamios deleted or never logged from lastlog!
Checking `chkutmp'...                                        The tty of the following user process(es) were not found
 in /var/run/utmp !
! RUID          PID TTY    CMD
! root          691 tty7   /usr/lib/xorg/Xorg -nolisten tcp -auth /var/run/sddm/{cead4972-a2f2-441e-be1f-8e9d47c18de4} -background none -noreset -displayfd 18 vt7
chkutmp: nothing deleted
Checking `OSX_RSPLUG'...                                    not infected

Especially these lines drew my attention:

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Searching for suspicious files and dirs, it may take a while... The following suspicious files and directories were found:  
/usr/lib/jvm/.java-1.8.0-openjdk-amd64.jinfo /usr/lib/python3/dist-packages/PyQt5/uic/widget-plugins/.noinit

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Checking `lkm'...                                           find: ‘/proc/4359/task/4359/net’: Invalid argument
find: ‘/proc/4359/net’: Invalid argument

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wlp2s0: PACKET SNIFFER(/sbin/wpa_supplicant[736], /sbin/wpa_supplicant[736], /sbin/dhclient[8907])

Code: Select all

Checking `wted'...                                          chkwtmp: nothing deleted

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Checking `z2'...                                            user lamios deleted or never logged from lastlog!
Checking `chkutmp'...                                        The tty of the following user process(es) were not found
 in /var/run/utmp !
! RUID          PID TTY    CMD
! root          691 tty7   /usr/lib/xorg/Xorg -nolisten tcp -auth /var/run/sddm/{cead4972-a2f2-441e-be1f-8e9d47c18de4} -background none -noreset -displayfd 18 vt7
chkutmp: nothing deleted

Before I had been able to update rkhunter, I had to make the following changes in the .conf: https://churchill.ddns.me.uk/post/rkhun ... on-option/
rkhunter.log:

For rkhunter, I thought these lines might be important:

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[00:18:06]   /usr/bin/lwp-request                            [ Warning ]
[00:18:06] Warning: The command '/usr/bin/lwp-request' has been replaced by a script: /usr/bin/lwp-request: Perl script text executable

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[00:18:46] Info: Starting test name 'filesystem'
[00:18:46] Performing filesystem checks
[00:18:46] Info: SCAN_MODE_DEV set to 'THOROUGH'
[00:18:47]   Checking /dev for suspicious file types         [ Warning ]
[00:18:47] Warning: Suspicious file types found in /dev:
[00:18:47]          /dev/shm/com.sophos.av.process.exclusion: data
[00:18:47]          /dev/shm/sem.com.sophos.av.process.exclusion: data
[00:18:47]   Checking for hidden files and directories       [ Warning ]
[00:18:47] Warning: Hidden directory found: /etc/.java

Is there a way to upload the rkhunter.log? The page seems not to accept any documents and the content is to long to post.

Does anybody know, if any of that stuff is concerning/how I get to know if I have to do something?

Thank you already for your help!

[GarryRicketson]

To upload the file so people can see it , use :
http://paste.debian.net/
or
https://pastebin.com/ and then include a link to the file in your post

[Lamios]

Thank you.

Alright, here is the link to the .log file from rkhunter: http://paste.debian.net/1036383/

[Lamios]

I just realised that I did not mention that I followed a phishing link I received from university

For rkunter it seems it is only useful when installed on a newly installed OS, so to late for me. Therefore, I installed Linux from the same ISO which I used to install my current OS, into a virtual machine, and run rkhunter and chkrootkit. Some of the warnings are identical, so I hope I can filter some out.

For rkhunter, the only one remaining is the following:

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[00:18:46] Info: Starting test name 'filesystem'
[00:18:46] Performing filesystem checks
[00:18:46] Info: SCAN_MODE_DEV set to 'THOROUGH'
[00:18:47]   Checking /dev for suspicious file types         [ Warning ]
[00:18:47] Warning: Suspicious file types found in /dev:
[00:18:47]          /dev/shm/com.sophos.av.process.exclusion: data
[00:18:47]          /dev/shm/sem.com.sophos.av.process.exclusion: data

I think I should probably install Sophos in the virtual machine to see if the warning occurs there too.

For chkrootkit ramain these two things:

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Checking `lkm'...                                           find: ‘/proc/4359/task/4359/net’: Invalid argument
find: ‘/proc/4359/net’: Invalid argument

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wlp2s0: PACKET SNIFFER(/sbin/wpa_supplicant[736], /sbin/wpa_supplicant[736], /sbin/dhclient[8907])

Concerning the wlan, I get a partially similar note in the virtual machine, but obviously it is using a different device to connect to the internet. I guess these two for chkrootkit are alright?

[Lamios]

0k, I installed Sophos in the virtual machine, and received the same warning about Sophos in rkhunter. So I think the outputs by rkhunter can be all explained.

I am actually not totally sure about the meaning of this two output pieces from chkrootkit:

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Checking `lkm'...                                           find: ‘/proc/4359/task/4359/net’: Invalid argument
find: ‘/proc/4359/net’: Invalid argument

and

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wlp2s0: PACKET SNIFFER(/sbin/wpa_supplicant[736], /sbin/wpa_supplicant[736], /sbin/dhclient[8907])

Is there anything I can do about the invalid argument?

Thank you!

[Lamios]

The folder 4359 seems not to exist in /proc. I don't know if it is bad that it does not exist, or if it can be totally normal.
Is there any information which I could add?

[Head_on_a_Stick]

The folder 4359 seems not to exist in /proc

^ This means that there is no process running with the ID of 4359.

[Lamios]

Thank you. I think then it is solved.