Rootkit scan results

Ask Fedora
1

Checking for backdoor ports [ Warning ]

What can I do to fix this does anybody know?
I dont know the command?
Ive got three warning from the scan.

Thanks for your help ahead of time

2

Very much depends on which ports the script is checking and complaining about, versus which ones you need open for inbound traffic.

Do you need to SSH into this box? If not, you don’t need port 22 open.
Does it run a web server, if not, you don’t need 80 and 445 open and so on.

From the output you have provided we can’t tell what it’s whinging about as a warning and without that info we can’t tell whether you can close them or not.

3

this is everything I’ve got:
hecking 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 ]
/usr/bin/adduser [ OK ]
/usr/bin/awk [ OK ]
/usr/bin/basename [ OK ]
/usr/bin/bash [ OK ]
/usr/bin/cat [ OK ]
/usr/bin/chattr [ OK ]
/usr/bin/chmod [ OK ]
/usr/bin/chown [ OK ]
/usr/bin/chroot [ OK ]
/usr/bin/cp [ OK ]
/usr/bin/curl [ OK ]
/usr/bin/cut [ OK ]
/usr/bin/date [ OK ]
/usr/bin/depmod [ OK ]
/usr/bin/df [ OK ]
/usr/bin/diff [ OK ]
/usr/bin/dirname [ OK ]
/usr/bin/dmesg [ OK ]
/usr/bin/dpkg [ OK ]
/usr/bin/dpkg-query [ OK ]
/usr/bin/du [ OK ]
/usr/bin/echo [ OK ]
/usr/bin/ed [ OK ]
/usr/bin/egrep [ Warning ]
/usr/bin/env [ OK ]
/usr/bin/fgrep [ Warning ]
/usr/bin/file [ OK ]
/usr/bin/find [ OK ]
/usr/bin/fsck [ OK ]
/usr/bin/fuser [ OK ]
/usr/bin/GET [ OK ]
/usr/bin/grep [ OK ]
/usr/bin/groupadd [ OK ]
/usr/bin/groupdel [ OK ]
/usr/bin/groupmod [ OK ]
/usr/bin/groups [ OK ]
/usr/bin/grpck [ OK ]
/usr/bin/head [ OK ]
/usr/bin/id [ OK ]
/usr/bin/ifconfig [ OK ]
/usr/bin/init [ OK ]
/usr/bin/insmod [ OK ]
/usr/bin/ip [ OK ]
/usr/bin/ipcs [ OK ]
/usr/bin/kill [ OK ]
/usr/bin/killall [ OK ]
/usr/bin/last [ OK ]
/usr/bin/ldd [ OK ]
/usr/bin/less [ OK ]
/usr/bin/locate [ OK ]
/usr/bin/logger [ OK ]
/usr/bin/login [ OK ]
/usr/bin/ls [ OK ]
/usr/bin/lsattr [ OK ]
/usr/bin/lsmod [ OK ]
/usr/bin/lsof [ OK ]
/usr/bin/mail [ OK ]
/usr/bin/md5sum [ OK ]
/usr/bin/mktemp [ OK ]
/usr/bin/modinfo [ OK ]
/usr/bin/modprobe [ OK ]
/usr/bin/more [ OK ]
/usr/bin/mount [ OK ]
/usr/bin/mv [ OK ]
/usr/bin/netstat [ OK ]
/usr/bin/newgrp [ OK ]
/usr/bin/nologin [ OK ]
/usr/bin/passwd [ OK ]
/usr/bin/perl [ OK ]
/usr/bin/pgrep [ OK ]
/usr/bin/ping [ OK ]
/usr/bin/pkill [ OK ]
/usr/bin/ps [ OK ]
/usr/bin/pstree [ OK ]
/usr/bin/pwck [ OK ]
/usr/bin/pwd [ OK ]
/usr/bin/readlink [ OK ]
/usr/bin/rkhunter [ OK ]
/usr/bin/rmmod [ OK ]
/usr/bin/route [ OK ]
/usr/bin/rpm [ OK ]
/usr/bin/rsyslogd [ OK ]
/usr/bin/runcon [ OK ]
/usr/bin/sed [ OK ]
/usr/bin/sestatus [ OK ]
/usr/bin/sh [ 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/sort [ OK ]
/usr/bin/ssh [ OK ]
/usr/bin/sshd [ OK ]
/usr/bin/stat [ OK ]
/usr/bin/strings [ OK ]
/usr/bin/su [ OK ]
/usr/bin/sudo [ OK ]
/usr/bin/sulogin [ OK ]
/usr/bin/sysctl [ OK ]
/usr/bin/tail [ OK ]
/usr/bin/test [ OK ]
/usr/bin/top [ OK ]
/usr/bin/touch [ OK ]
/usr/bin/tr [ OK ]
/usr/bin/uname [ OK ]
/usr/bin/uniq [ OK ]
/usr/bin/useradd [ OK ]
/usr/bin/userdel [ OK ]
/usr/bin/usermod [ OK ]
/usr/bin/users [ OK ]
/usr/bin/vipw [ 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/numfmt [ OK ]
/usr/bin/gawk [ OK ]
/usr/bin/kmod [ OK ]
/usr/bin/plocate [ OK ]
/usr/bin/s-nail [ OK ]
/usr/bin/wget2 [ OK ]
/usr/bin/whatis.man-db [ OK ]
/usr/libexec/gawk [ OK ]
/usr/lib/systemd/systemd [ 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 ]
Diamorphine LKM [ Not found ]
Dica-Kit Rootkit [ Not found ]
Dreams Rootkit [ Not found ]
Duarawkz Rootkit [ Not found ]
Ebury backdoor [ Not found ]
Enye LKM [ Not found ]
Flea Linux 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 ]
IntoXonia-NG Rootkit [ Not found ]
Irix Rootkit [ Not found ]
Jynx Rootkit [ Not found ]
Jynx2 Rootkit [ Not found ]
KBeast 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 ]
Mokes backdoor [ 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 ]
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 ]
zaRwT.KiT Rootkit [ Not found ]
ZK Rootkit [ Not found ]

[Press to continue]

Performing additional rootkit checks
Suckit Rootkit 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 hidden processes                            \[ Skipped \] 
Checking for login backdoors                             \[ None found \] 
Checking for sniffer log files                           \[ None found \] 
Checking for suspicious directories                      \[ None found \] 
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 ]

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 [ None found ]
Checking for group file changes [ None found ]
Checking root account shell history files [ None found ]

Performing system configuration file checks
Checking for an SSH configuration file [ Found ]
Checking if SSH root access is allowed [ Not set ]
Checking if SSH protocol v1 is allowed [ Not set ]
Checking for other suspicious configuration settings [ None found ]
Checking for a running system logging daemon [ Found ]
Checking for a system logging configuration file [ Found ]
Checking if syslog remote logging is allowed [ Not allowed ]

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

[Press to continue]

System checks summary

File properties checks…
Required commands check failed
Files checked: 132
Suspect files: 2

Rootkit checks…
Rootkits checked : 498
Possible rootkits: 0

Applications checks…
All checks skipped

The system checks took: 2 minutes and 6 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)

Penguinista@unknown5207850BF844:~$

Thank you so much Rick

4

The warnings for /usr/bin/egrep and /usr/bin/fgrep are false positives and indicate no compromise. These files are not malicious; they are standard POSIX shell scripts provided by the grep package for backward compatibility.

  • Cause: The rkhunter tool flags these because it expects compiled binaries, not shell scripts.

  • Verification: You can verify their legitimacy by checking their content with cat /usr/bin/egrep, which will show a simple script calling grep -E.

  • Resolution: These warnings are harmless. To suppress them, you can update the rkhunter baseline by running sudo rkhunter --propupd, or whitelist the scripts in /etc/rkhunter.conf using SCRIPTWHITELIST=/usr/bin/egrep and SCRIPTWHITELIST=/usr/bin/fgrep.

Mine:

cat /usr/bin/egrep && cat /usr/bin/fgrep
#!/usr/bin/sh
cmd=${0##*/}
echo "$cmd: warning: $cmd is obsolescent; using grep -E" >&2
exec grep -E "$@"
#!/usr/bin/sh
cmd=${0##*/}
echo "$cmd: warning: $cmd is obsolescent; using grep -F" >&2
exec grep -F "$@"