What is rootkit:-
A rootkit is a stealthy type of software, often malicious, designed to hide the existence of certain processes or programs from normal methods of detection and enable continued privileged access to a computer. The term rootkit is a concatenation of “root” (the traditional name of the privileged account on Unix operating systems) and the word “kit” (which refers to the software components that implement the tool). The term “rootkit” has negative connotations through its association with malware.
Rootkit installation can be automated, or an attacker can install it once they’ve obtained root or Administrator access. Obtaining this access is a result of direct attack on a system (i.e. exploiting a known vulnerability, password (either by cracking, privilege escalation, or social engineering)). Once installed it becomes possible to hide the intrusion as well as to maintain privileged access. Like any software they can have a good purpose or a malicious purpose. The key is the root/Administrator access. Full control over a system means that existing software can be modified, including software that might otherwise be used to detect or circumvent it.
rkhunter software Description:-
rkhunter is a shell script which carries out various checks on the
local system to try and detect known rootkits and malware. It also per‐
forms checks to see if commands have been modified, if the system
startup files have been modified, and various checks on the network
interfaces, including checks for listening applications.
rkhunter has been written to be as generic as possible, and so should
run on most Linux and UNIX systems. It is provided with some support
scripts should certain commands be missing from the system, and some of these are perl scripts. rkhunter does require certain commands to be present for it to be able to execute. Additionally, some tests require specific commands, but if these are not present then the test will be skipped. rkhunter needs to be run under a Bourne-type shell, typically bash or ksh. rkhunter can be run as a cron job or from the com mand-line.
Installation:-
[root@ramank ~]# yum install rkhunter.noarch
Loaded plugins: langpacks, presto, refresh-packagekit
Setting up Install Process
Resolving Dependencies
–> Running transaction check
—> Package rkhunter.noarch 0:1.3.8-12.fc16 will be installed
–> Finished Dependency Resolution
Dependencies Resolved
================================================================================
Package Arch Version Repository Size
================================================================================
Installing:
rkhunter noarch 1.3.8-12.fc16 updates 181 k
Transaction Summary
================================================================================
Install 1 Package
Total download size: 181 k
Installed size: 734 k
Is this ok [y/N]: y
Downloading Packages:
rkhunter-1.3.8-12.fc16.noarch.rpm | 181 kB 00:00
Running Transaction Check
Running Transaction Test
Transaction Test Succeeded
Running Transaction
Installing : rkhunter-1.3.8-12.fc16.noarch 1/1
Installed:
rkhunter.noarch 0:1.3.8-12.fc16
Complete! :-
Following command option tells rkhunter to perform various checks on the local system.
[root@ramank ~]# rkhunter –check
[ Rootkit Hunter version 1.3.8 ]
Checking system commands…
Performing ‘strings’ command checks
Checking ‘strings’ command [ OK ]
Performing ‘shared libraries’ checks
Checking for preloading variables [ None found ]
Checking for preloaded libraries [ None found ]
Checking LD_LIBRARY_PATH variable [ Not found ]
Performing file properties checks
Checking for prerequisites [ Warning ]
/sbin/chkconfig [ OK ]
/sbin/depmod [ OK ]
/sbin/fsck [ OK ]
/sbin/fuser [ 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/nologin [ OK ]
/sbin/rmmod [ OK ]
/sbin/route [ OK ]
/sbin/rsyslogd [ OK ]
/sbin/runlevel [ OK ]
/sbin/sulogin [ OK ]
/sbin/sysctl [ OK ]
/bin/awk [ OK ]
/bin/basename [ OK ]
/bin/bash [ OK ]
/bin/cat [ OK ]
/bin/chmod [ OK ]
/bin/chown [ OK ]
/bin/cp [ OK ]
/bin/cut [ OK ]
/bin/date [ OK ]
/bin/df [ OK ]
/bin/dmesg [ OK ]
/bin/echo [ OK ]
/bin/ed [ OK ]
/bin/egrep [ OK ]
/bin/env [ OK ]
/bin/fgrep [ OK ]
/bin/find [ OK ]
/bin/grep [ OK ]
/bin/kill [ OK ]
/bin/login [ OK ]
/bin/ls [ OK ]
/bin/mail [ 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/rpm [ OK ]
/bin/sed [ OK ]
/bin/sh [ OK ]
/bin/sort [ OK ]
/bin/su [ OK ]
/bin/touch [ OK ]
/bin/uname [ OK ]
/bin/systemd [ OK ]
/bin/systemctl [ OK ]
/bin/gawk [ OK ]
/bin/mailx [ OK ]
/usr/sbin/adduser [ OK ]
/usr/sbin/chroot [ OK ]
/usr/sbin/groupadd [ OK ]
/usr/sbin/groupdel [ OK ]
/usr/sbin/groupmod [ OK ]
/usr/sbin/grpck [ OK ]
/usr/sbin/lsof [ OK ]
/usr/sbin/prelink [ OK ]
/usr/sbin/pwck [ OK ]
/usr/sbin/sestatus [ 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 ]
/usr/bin/awk [ OK ]
/usr/bin/chattr [ OK ]
/usr/bin/curl [ OK ]
/usr/bin/cut [ OK ]
/usr/bin/diff [ OK ]
/usr/bin/dirname [ OK ]
/usr/bin/du [ OK ]
/usr/bin/elinks [ 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/kill [ OK ]
/usr/bin/killall [ OK ]
/usr/bin/last [ OK ]
/usr/bin/lastlog [ OK ]
/usr/bin/ldd [ OK ]
/usr/bin/less [ OK ]
/usr/bin/links [ OK ]
/usr/bin/locate [ OK ]
/usr/bin/logger [ OK ]
/usr/bin/lsattr [ OK ]
/usr/bin/md5sum [ OK ]
/usr/bin/newgrp [ OK ]
/usr/bin/passwd [ OK ]
/usr/bin/perl [ OK ]
/usr/bin/pgrep [ OK ]
/usr/bin/pstree [ OK ]
/usr/bin/readlink [ OK ]
/usr/bin/rkhunter [ OK ]
/usr/bin/runcon [ OK ]
/usr/bin/sha1sum [ OK ]
/usr/bin/sha224sum [ OK ]
/usr/bin/sha256sum [ OK ]
/usr/bin/sha384sum [ OK ]
/usr/bin/sha512sum [ OK ]
/usr/bin/size [ 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/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 ]
[Press 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 ]
Adore 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 ]
cb 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 ]
Fu Rootkit [ Not found ]
Fuck`it Rootkit [ Not found ]
GasKit Rootkit [ Not found ]
Heroin LKM [ Not found ]
HjC Kit [ Not found ]
ignoKit Rootkit [ Not found ]
iLLogiC Rootkit [ Not found ]
IntoXonia-NG Rootkit [ Not found ]
Irix Rootkit [ Not found ]
Kitko Rootkit [ Not found ]
Knark Rootkit [ Not found ]
ld-linuxv.so 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 ]
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 ]
‘Spanish’ 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 ]
trNkit 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 ]
Xzibit Rootkit [ Not found ]
X-Org SunOS Rootkit [ Not found ]
zaRwT.KiT Rootkit [ Warning ]
ZK 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 [ None found ]
Checking for Apache backdoor [ Not found ]
Performing Linux specific checks
Checking loaded kernel modules [ OK ]
Checking kernel module names [ OK ]
[Press to continue]
Checking the network…
Performing checks on the network ports
Checking for backdoor ports [ None found ]
Checking for hidden ports [ Skipped ]
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 [ Not set ]
Checking if SSH protocol v1 is allowed [ Not set ]
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 to continue]
System checks summary
=====================
File properties checks…
Required commands check failed
Files checked: 138
Suspect files: 0
Rootkit checks…
Rootkits checked : 249
Possible rootkits: 1
Rootkit names : zaRwT.KiT Rootkit
Applications checks…
All checks skipped
The system checks took: 3 minutes and 13 seconds
All results have been written to the log file (/var/log/rkhunter/rkhunter.log)
One or more warnings have been found while checking the system.
Please check the log file (/var/log/rkhunter/rkhunter.log)
P.S :- Warning: zaRwT.KiT Rootkit [ Warning ]
Directory ‘/rk’ found
rk Dir exist under /
drwxr-xr-x 2 root root 4.0K Apr 23 2012 rk
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