Contents
Suricata
SURICATA IDS/IPS is an open source IDS that monitors communications on the network and detects suspicious traffic.
The basic mechanism is signature-based, so it can detect predefined unauthorized communications. Suricata is also characterized by its ability to provide protection as well as detection.
1.advance preparation
①Activate the EPEL Repository
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# dnf -y install epel-release |
②System updates
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# dnf update -y |
2.Suricata Installation and Configuration
①Suricata Install
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# dnf install suricata Check Version # suricata -V This is Suricata version 6.0.12 RELEASE |
②Determine interface and IP address where Suricata will inspect network packets
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# ip --brief add lo UNKNOWN 127.0.0.1/8 ::1/128 ens160 UP 192.168.11.83/24 fe80::xxx:xxxx:xxxx:xxx/xx |
③Edit configuration file
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# vi /etc/suricata/suricata.yaml # Line 15 : In the "vars" section, define the network HOME_NET: "[192.168.11.0/24]" EXTRNAL_NET: "!$HOME_NET" # Line 589 : Set interface name in "af-packet" section af-packet: - interface: ens160 |
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# vi /etc/sysconfig/suricata # Line 8 :Specify interface # Add options to be passed to the daemon OPTIONS="-i ens160 --user suricata " |
④Suricata rules update
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# suricata-update |
⑤Activate Suricata
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# systemctl enable --now suricata Created symlink /etc/systemd/system/multiuser.target.wants/suricata.service → /usr/lib/systemd/system/suricata.service. |
⑥Confirm Suricata startup
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# systemctl status suricata ● suricata.service - Suricata Intrusion Detection Service Loaded: loaded (/usr/lib/systemd/system/suricata.service; enabled; preset:> Active: active (running) since Sun 2023-05-28 08:54:30 JST; 7s ago Docs: man:suricata(1) Process: 4854 ExecStartPre=/bin/rm -f /var/run/suricata.pid (code=exited, s> Main PID: 4855 (Suricata-Main) Tasks: 1 (limit: 22993) Memory: 229.1M CPU: 7.894s CGroup: /system.slice/suricata.service mq4855 /sbin/suricata -c /etc/suricata/suricata.yaml --pidfile /va> May 28 08:54:30 Lepard systemd[1]: Starting Suricata Intrusion Detection Servic> May 28 08:54:30 Lepard systemd[1]: Started Suricata Intrusion Detection Servic |
Check Log
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# tail /var/log/suricata/suricata.log 28/5/2023 -- 08:54:30 - <Info> - stats output device (regular) initialized: stats.log 28/5/2023 -- 08:54:30 - <Info> - Running in live mode, activating unix socket 28/5/2023 -- 08:54:41 - <Info> - 1 rule files processed. 33831 rules successfully loaded, 0 rules failed 28/5/2023 -- 08:54:41 - <Info> - Threshold config parsed: 0 rule(s) found 28/5/2023 -- 08:54:42 - <Info> - 33834 signatures processed. 1246 are IP-only rules, 5200 are inspecting packet payload, 27181 inspect application layer, 108 are decoder event only 28/5/2023 -- 08:54:49 - <Info> - Going to use 2 thread(s) 28/5/2023 -- 08:54:49 - <Info> - Running in live mode, activating unix socket 28/5/2023 -- 08:54:49 - <Info> - Using unix socket file '/var/run/suricata/suricata-command.socket' 28/5/2023 -- 08:54:49 - <Notice> - all 2 packet processing threads, 4 management threads initialized, engine started. 28/5/2023 -- 08:54:49 - <Info> - All AFP capture threads are running. |
Check the stats.log file for statistics (updated every 8 seconds by default)
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# tail -f /var/log/suricata/stats.log |
A more advanced output, EVE JSON, can be generated with the following command
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# tail -f /var/log/suricata/eve.json |
3.Suricata Testing
①Run ping test with curl utility
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# curl http://testmynids.org/uid/index.html uid=0(root) gid=0(root) groups=0(root) |
②Check the alert log to see if it has been logged
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# cat /var/log/suricata/fast.log 05/28/2023-09:02:35.229044 [**] [1:2013028:7] ET POLICY curl User-Agent Outbound [**] [Classification: Attempted Information Leak] [Priority: 2] {TCP} 192.168.11.83:55648 -> 18.65.159.104:80 05/28/2023-09:02:35.242726 [**] [1:2100498:7] GPL ATTACK_RESPONSE id check returned root [**] [Classification: Potentially Bad Traffic] [Priority: 2] {TCP} 18.65.159.104:80 -> 192.168.11.83:55648 |
4.Setting Suricata Rules
①Display of rule sets packaged in Suricata
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# ls -al /var/lib/suricata/rules/ total 24520 drwxr-s--- 2 root suricata 57 May 28 08:51 . drwxrws--- 4 suricata suricata 33 May 28 08:51 .. -rw-r--r-- 1 root suricata 3228 May 28 08:51 classification.config -rw-r--r-- 1 root suricata 25102338 May 28 08:51 suricata.rules |
②Index list of sources providing rule sets
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# suricata-update list-sources Name: et/open Vendor: Proofpoint Summary: Emerging Threats Open Ruleset License: MIT Name: et/pro Vendor: Proofpoint Summary: Emerging Threats Pro Ruleset License: Commercial Replaces: et/open Parameters: secret-code Subscription: https://www.proofpoint.com/us/threat-insight/et-pro-ruleset Name: oisf/trafficid Vendor: OISF Summary: Suricata Traffic ID ruleset License: MIT Name: scwx/enhanced Vendor: Secureworks Summary: Secureworks suricata-enhanced ruleset License: Commercial Parameters: secret-code Subscription: https://www.secureworks.com/contact/ (Please reference CTU Countermeasures) Name: scwx/malware Vendor: Secureworks Summary: Secureworks suricata-malware ruleset License: Commercial Parameters: secret-code Subscription: https://www.secureworks.com/contact/ (Please reference CTU Countermeasures) Name: scwx/security Vendor: Secureworks Summary: Secureworks suricata-security ruleset License: Commercial Parameters: secret-code Subscription: https://www.secureworks.com/contact/ (Please reference CTU Countermeasures) Name: sslbl/ssl-fp-blacklist Vendor: Abuse.ch Summary: Abuse.ch SSL Blacklist License: Non-Commercial Name: sslbl/ja3-fingerprints Vendor: Abuse.ch Summary: Abuse.ch Suricata JA3 Fingerprint Ruleset License: Non-Commercial Name: etnetera/aggressive Vendor: Etnetera a.s. Summary: Etnetera aggressive IP blacklist License: MIT Name: tgreen/hunting Vendor: tgreen Summary: Threat hunting rules License: GPLv3 Name: malsilo/win-malware Vendor: malsilo Summary: Commodity malware rules License: MIT Name: stamus/lateral Vendor: Stamus Networks Summary: Lateral movement rules License: GPL-3.0-only |
③Enable source (if et/open is enabled)
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# suricata-update enable-source et/open 28/5/2023 -- 09:04:33 - <Info> -- Using data-directory /var/lib/suricata. 28/5/2023 -- 09:04:33 - <Info> -- Using Suricata configuration /etc/suricata/suricata.yaml 28/5/2023 -- 09:04:33 - <Info> -- Using /usr/share/suricata/rules for Suricata provided rules. 28/5/2023 -- 09:04:33 - <Info> -- Found Suricata version 6.0.12 at /usr/sbin/suricata. 28/5/2023 -- 09:04:33 - <Info> -- Creating directory /var/lib/suricata/update/sources 28/5/2023 -- 09:04:33 - <Info> -- Source et/open enabled |
Perform update
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# suricata-update |
Restart Suricata service
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# systemctl restart suricata |
5.Creating Suricata Custom Rules
①Create files containing customer rules
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# vi /etc/suricata/rules/local.rules Include the following information alert icmp any any -> $HOME_NET any (msg:"ICMP Ping"; sid:1; rev:1;) |
②Edit configuration file (define new rule paths)
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# vi /etc/suricata/suricata.yaml # Added around line 1932 default-rule-path: /var/lib/suricata/rules rule-files: - suricata.rules - /etc/suricata/rules/local.rules |
③Testing the configuration file
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# suricata -T -c /etc/suricata/suricata.yaml -v 28/5/2023 -- 09:08:07 - <Info> - Running suricata under test mode 28/5/2023 -- 09:08:07 - <Notice> - This is Suricata version 6.0.12 RELEASE running in SYSTEM mode 28/5/2023 -- 09:08:07 - <Info> - CPUs/cores online: 2 28/5/2023 -- 09:08:07 - <Info> - Setting engine mode to IDS mode by default 28/5/2023 -- 09:08:07 - <Info> - fast output device (regular) initialized: fast.log 28/5/2023 -- 09:08:07 - <Info> - eve-log output device (regular) initialized: eve.json 28/5/2023 -- 09:08:07 - <Info> - stats output device (regular) initialized: stats.log 28/5/2023 -- 09:08:19 - <Info> - 2 rule files processed. 33832 rules successfully loaded, 0 rules failed 28/5/2023 -- 09:08:19 - <Info> - Threshold config parsed: 0 rule(s) found 28/5/2023 -- 09:08:19 - <Info> - 33835 signatures processed. 1247 are IP-only rules, 5200 are inspecting packet payload, 27181 inspect application layer, 108 are decoder event only 28/5/2023 -- 09:08:27 - <Notice> - Configuration provided was successfully loaded. Exiting. 28/5/2023 -- 09:08:27 - <Info> - cleaning up signature grouping structure... complete |
Restart Suricat service
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# systemctl restart suricata |
④Testing the application of Custom Rules
Ping another device on the same local network to see if it was logged
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# cat /var/log/suricata/fast.log 05/28/2023-09:02:35.229044 [**] [1:2013028:7] ET POLICY curl User-Agent Outbound [**] [Classification: Attempted Information Leak] [Priority: 2] {TCP} 192.168.11.83:55648 -> 18.65.159.104:80 05/28/2023-09:02:35.242726 [**] [1:2100498:7] GPL ATTACK_RESPONSE id check returned root [**] [Classification: Potentially Bad Traffic] [Priority: 2] {TCP} 18.65.159.104:80 -> 192.168.11.83:55648 |
To get logs in JSON format, install jq on your system
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# dnf install jq |
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# systemctl restart suricata |
Execute the following command to ping another device on the same local network
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# tail -f /var/log/suricata/eve.json | jq 'select(.event_type=="alert")' When ping is executed, the following is displayed in the console { "timestamp": "2023-05-28T09:10:34.895931+0900", "flow_id": 1466544969919419, "in_iface": "ens160", "event_type": "alert", "src_ip": "192.168.11.22", "src_port": 0, "dest_ip": "192.168.11.83", "dest_port": 0, "proto": "ICMP", "icmp_type": 8, "icmp_code": 0, "alert": { "action": "allowed", "gid": 1, "signature_id": 1, "rev": 1, "signature": "ICMP Ping", "category": "", "severity": 3 }, "flow": { "pkts_toserver": 1, "pkts_toclient": 0, "bytes_toserver": 74, "bytes_toclient": 0, "start": "2023-05-28T09:10:34.895931+0900" } } { "timestamp": "2023-05-28T09:10:34.896018+0900", "flow_id": 1466544969919419, "in_iface": "ens160", "event_type": "alert", "src_ip": "192.168.11.83", "src_port": 0, "dest_ip": "192.168.11.22", "dest_port": 0, "proto": "ICMP", "icmp_type": 0, "icmp_code": 0, "alert": { "action": "allowed", "gid": 1, "signature_id": 1, "rev": 1, "signature": "ICMP Ping", "category": "", "severity": 3 }, "flow": { "pkts_toserver": 1, "pkts_toclient": 1, "bytes_toserver": 74, "bytes_toclient": 74, "start": "2023-05-28T09:10:34.895931+0900" } } |
Tripwire
1.Installation
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# dnf install -y tripwire |
2.Passphrase setting
Set site passphrase and local passphrase
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# tripwire-setup-keyfiles |
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---------------------------------------------- The Tripwire site and local passphrases are used to sign a variety of files, such as the configuration, policy, and database files. Passphrases should be at least 8 characters in length and contain both letters and numbers. See the Tripwire manual for more information. ---------------------------------------------- Creating key files... (When selecting a passphrase, keep in mind that good passphrases typically have upper and lower case letters, digits and punctuation marks, and are at least 8 characters in length.) Enter the site keyfile passphrase: ←Enter any "Site Passphrase" Verify the site keyfile passphrase: ←Enter "Site Passphrase" again Generating key (this may take several minutes)...Key generation complete. (When selecting a passphrase, keep in mind that good passphrases typically have upper and lower case letters, digits and punctuation marks, and are at least 8 characters in length.) Enter the local keyfile passphrase: ←Enter any "local passphrase" Verify the local keyfile passphrase: ←Enter "Local Passphrase" again Generating key (this may take several minutes)...Key generation complete. ---------------------------------------------- Signing configuration file... Please enter your site passphrase: ←Enter "Site Passphrase" Wrote configuration file: /etc/tripwire/tw.cfg A clear-text version of the Tripwire configuration file: /etc/tripwire/twcfg.txt has been preserved for your inspection. It is recommended that you move this file to a secure location and/or encrypt it in place (using a tool such as GPG, for example) after you have examined it. ---------------------------------------------- Signing policy file... Please enter your site passphrase: ←Enter "Site Passphrase" Wrote policy file: /etc/tripwire/tw.pol A clear-text version of the Tripwire policy file: /etc/tripwire/twpol.txt ～omission～ default values from the current configuration file are used. |
3.Tripwire Configuration
①Configuration File Edit
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# vi /etc/tripwire/twcfg.txt ●Per line 9 Add "#" at the beginning of the line and "LOOSEDIRECTORYCHECKING =true" on the line below it ●Per line 12 Add "#" at the beginning of the line and "REPORTLEVEL =4" on the line below it. Level 4 provides the most detailed report of the five levels from "0" to "4". #REPORTLEVEL =3 REPORTLEVEL =4 |
②Create a Tripwire configuration file (cryptographically signed version)
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# twadmin -m F -c /etc/tripwire/tw.cfg -S /etc/tripwire/site.key /etc/tripwire/twcfg.txt Please enter your site passphrase: ←Enter site passphrase" Wrote configuration file: /etc/tripwire/tw.cfg |
③Delete Tripwire configuration file (text version)
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# rm -f /etc/tripwire/twcfg.txt |
④Policy File Settings
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# cd /etc/tripwire/ # vi twpolmake.pl |
Contents of twpolmake.pl
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#!/usr/bin/perl # Tripwire Policy File customize tool # $POLFILE=$ARGV[0]; open(POL,"$POLFILE") or die "open error: $POLFILE" ; my($myhost,$thost) ; my($sharp,$tpath,$cond) ; my($INRULE) = 0 ; while (<POL>) { chomp; if (($thost) = /^HOSTNAME\s*=\s*(.*)\s*;/) { $myhost = `hostname` ; chomp($myhost) ; if ($thost ne $myhost) { $_="HOSTNAME=\"$myhost\";" ; } } elsif ( /^{/ ) { $INRULE=1 ; } elsif ( /^}/ ) { $INRULE=0 ; } elsif ($INRULE == 1 and ($sharp,$tpath,$cond) = /^(\s*\#?\s*)(\/\S+)\b(\s+->\s+.+)$/) { $ret = ($sharp =~ s/\#//g) ; if ($tpath eq '/sbin/e2fsadm' ) { $cond =~ s/;\s+(tune2fs.*)$/; \#$1/ ; } if (! -s $tpath) { $_ = "$sharp#$tpath$cond" if ($ret == 0) ; } else { $_ = "$sharp$tpath$cond" ; } } print "$_\n" ; } close(POL) ; |
⑤Policy File Optimizations
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# perl /etc/tripwire/twpolmake.pl /etc/tripwire/twpol.txt > /etc/tripwire/twpol.txt.new |
⑥Create policy file (cryptographically signed version) based on optimized policy file
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# twadmin -m P -c /etc/tripwire/tw.cfg -p /etc/tripwire/tw.pol -S /etc/tripwire/site.key /etc/tripwire/twpol.txt.new Please enter your site passphrase: ←Enter site passphrase Wrote policy file: /etc/tripwire/tw.pol |
⑦Create database and check operation
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# tripwire -m i -s -c /etc/tripwire/tw.cfg Please enter your local passphrase: ←Enter local passphrase |
Create test files
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# echo test > /root/test.txt |
Check Tripwire operation
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# tripwire -m c -s -c /etc/tripwire/tw.cfg OK if it appears as follows Open Source Tripwire(R) 2.4.3.7 Integrity Check Report Report generated by: root Report created on: Sun 28 May 2023 09:28:42 AM JST Database last updated on: Never =============================================================================== Report Summary: =============================================================================== Host name: Lepard Host IP address: 192.168.11.83 Host ID: None Policy file used: /etc/tripwire/tw.pol Configuration file used: /etc/tripwire/tw.cfg Database file used: /var/lib/tripwire/Lepard.twd Command line used: tripwire -m c -s -c /etc/tripwire/tw.cfg =============================================================================== Rule Summary: =============================================================================== ------------------------------------------------------------------------------- Section: Unix File System ------------------------------------------------------------------------------- Rule Name Severity Level Added Removed Modified --------- -------------- ----- ------- -------- User binaries 66 0 0 0 Tripwire Binaries 100 0 0 0 Libraries 66 0 0 0 Operating System Utilities 100 0 0 0 File System and Disk Administraton Programs 100 0 0 0 Kernel Administration Programs 100 0 0 0 Networking Programs 100 0 0 0 System Administration Programs 100 0 0 0 Hardware and Device Control Programs 100 0 0 0 System Information Programs 100 0 0 0 (/sbin/runlevel) Application Information Programs 100 0 0 0 (/sbin/rtmon) Critical Utility Sym-Links 100 0 0 0 Shell Binaries 100 0 0 0 Critical system boot files 100 0 0 0 * Tripwire Data Files 100 1 0 0 System boot changes 100 0 0 0 OS executables and libraries 100 0 0 0 Security Control 100 0 0 0 Login Scripts 100 0 0 0 Critical configuration files 100 0 0 0 * Root config files 100 1 0 0 Invariant Directories 66 0 0 0 Temporary directories 33 0 0 0 Critical devices 100 0 0 0 (/proc/kcore) Total objects scanned: 33118 Total violations found: 2 =============================================================================== Object Summary: =============================================================================== ------------------------------------------------------------------------------- # Section: Unix File System ------------------------------------------------------------------------------- ------------------------------------------------------------------------------- Rule Name: Tripwire Data Files (/var/lib/tripwire) Severity Level: 100 ------------------------------------------------------------------------------- Added: "/var/lib/tripwire/Lepard.twd" ------------------------------------------------------------------------------- Rule Name: Root config files (/root) Severity Level: 100 ------------------------------------------------------------------------------- Added: "/root/test.txt" =============================================================================== Error Report: =============================================================================== No Errors ------------------------------------------------------------------------------- *** End of report *** Open Source Tripwire 2.4 Portions copyright 2000-2018 Tripwire, Inc. Tripwire is a registered trademark of Tripwire, Inc. This software comes with ABSOLUTELY NO WARRANTY; for details use --version. This is free software which may be redistributed or modified only under certain conditions; see COPYING for details. All rights reserved. |
Delete test files
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# rm -f /root/test.txt |
⑧Tripwire Scheduled Scripts
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# cd /var/www/system # vi tripwire.sh |
Contents of tripwire.sh
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#!/bin/bash PATH=/usr/sbin:/usr/bin:/bin:/usr/local/tripwire/sbin # Passphrase setting LOCALPASS= ←local passphrase SITEPASS= ←site passphrase cd /etc/tripwire # Tripwire check run tripwire -m c -s -c tw.cfg|mail -s "Tripwire(R) Integrity Check Report in `hostname`" root # Policy File Update twadmin -m p -c tw.cfg -p tw.pol -S site.key > twpol.txt perl twpolmake.pl twpol.txt > twpol.txt.new twadmin -m P -c tw.cfg -p tw.pol -S site.key -Q $SITEPASS twpol.txt.new > /dev/null rm -f twpol.txt* *.bak # Database Update rm -f /usr/local/tripwire/lib/tripwire/*.twd* tripwire -m i -s -c tw.cfg -P $LOCALPASS |
⑨Tripwire Autorun Script Execution Settings
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# chmod 700 tripwire.sh Add to cron # crontab -e 0 3 * * * /var/www/system/tripwire.sh |
Reference: Script for reporting results by e-mail
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#!/bin/bash PATH=/usr/sbin:/usr/bin:/bin:/usr/local/tripwire/sbin # Passphrase setting LOCALPASS=xxxxx # local passphrase SITEPASS=xxxxx # site passphrase #Specify e-mail address for notification MAIL="<your mailaddress> " cd /etc/tripwire # Tripwire check run tripwire -m c -s -c tw.cfg|mail -s "Tripwire(R) Integrity Check Report in `hostname`" $MAIL # Policy File Update twadmin -m p -c tw.cfg -p tw.pol -S site.key > twpol.txt perl twpolmake.pl twpol.txt > twpol.txt.new twadmin -m P -c tw.cfg -p tw.pol -S site.key -Q $SITEPASS twpol.txt.new > /dev/null rm -f twpol.txt* *.bak # Database update rm -f /usr/local/tripwire/lib/tripwire/*.twd* tripwire -m i -s -c tw.cfg -P $LOCALPASS |
Confirmation that the results of the tripwire execution are notified to the specified e-mail address
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# /var/www/system/tripwire.sh |
Chkrootkit
①Download and install chkrootkit
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# cd /usr/local/src # wget ftp://ftp.chkrootkit.org/pub/seg/pac/chkrootkit.tar.gz # tar xvf chkrootkit.tar.gz |
➁Create /root/bin directory and move chkrootkit command to that directory
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# mkdir -p /root/bin # mv chkrootkit-0.57/chkrootkit /root/bin |
➂Check chkrootkit.
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# chkrootkit | grep INFECTED |
Checking `chsh'... INFECTED
If the above display appears, it is probably a false positive.
④Create chkrootkit periodic execution script and change permissions
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# vi /etc/cron.daily/chkrootkit |
Scheduled Script Contents
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#!/bin/bash PATH=/usr/bin:/bin:/root/bin LOG=/tmp/$(basename ${0}) # Run chkrootkit chkrootkit > $LOG 2>&1 # log output cat $LOG | logger -t $(basename ${0}) # SMTPS bindshell false positive response if [ ! -z "$(grep 465 $LOG)" ] && \ [ -z $(/usr/sbin/lsof -i:465|grep bindshell) ]; then sed -i '/465/d' $LOG fi # Support for Suckit false positives when updating upstart package if [ ! -z "$(grep Suckit $LOG)" ] && \ [ -z "$(rpm -V `rpm -qf /sbin/init`)" ]; then sed -i '/Suckit/d' $LOG fi # Send mail to root only when rootkit is detected [ ! -z "$(grep INFECTED $LOG)" ] && \ grep INFECTED $LOG | mail -s "chkrootkit report in `hostname`" root |
Add execution permission to chkrootkit execution script
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# chmod 700 /etc/cron.daily/chkrootkit |
⑥Backup commands used by chkrootkit
If the commands used by chkrootkit are tampered with, rootkit will not be detected.
Back up these commands.
If necessary, run chkrootkit with the backed up command
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# cd /root # mkdir /root/chkrootkit_cmd # cp `which --skip-alias awk cut echo egrep grep find head id ls netstat ps strings sed ssh uname` chkrootkit_cmd/ # ls -l /root/chkrootkit_cmd/ total 2616 -rwxr-xr-x 1 root root 714968 May 28 09:48 awk -rwxr-xr-x 1 root root 48760 May 28 09:48 cut -rwxr-xr-x 1 root root 36144 May 28 09:48 echo -rwxr-xr-x 1 root root 32 May 28 09:48 egrep -rwxr-xr-x 1 root root 292760 May 28 09:48 find -rwxr-xr-x 1 root root 44648 May 28 09:48 head -rwxr-xr-x 1 root root 40472 May 28 09:48 id -rwxr-xr-x 1 root root 140760 May 28 09:48 ls -rwxr-xr-x 1 root root 161624 May 28 09:48 netstat -rwxr-xr-x 1 root root 144432 May 28 09:48 ps -rwxr-xr-x 1 root root 116736 May 28 09:48 sed -rwxr-xr-x 1 root root 851208 May 28 09:48 ssh -rwxr-xr-x 1 root root 32504 May 28 09:48 strings -rwxr-xr-x 1 root root 32232 May 28 09:48 uname |
⑦Run chkrootkit on the copied command
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# chkrootkit -p /root/chkrootkit_cmd | grep INFECTED |
If nothing is displayed, no problem.
⑧Compresses backed up commands
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# tar zcvf chkrootkit_cmd.tar.gz chkrootkit_cmd chkrootkit_cmd/ chkrootkit_cmd/awk chkrootkit_cmd/cut chkrootkit_cmd/echo chkrootkit_cmd/egrep chkrootkit_cmd/find chkrootkit_cmd/head chkrootkit_cmd/id chkrootkit_cmd/ls chkrootkit_cmd/netstat chkrootkit_cmd/ps chkrootkit_cmd/strings chkrootkit_cmd/sed chkrootkit_cmd/ssh chkrootkit_cmd/uname chkrootkit_cmd/grep |
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# ls -l total 1280 -rw-------. 1 root root 1201 May 24 22:46 anaconda-ks.cfg drwxr-xr-x 2 root root 24 May 28 09:41 bin drwxr-xr-x 2 root root 184 May 28 09:52 chkrootkit_cmd -rw-r--r-- 1 root root 1296351 May 28 09:53 chkrootkit_cmd.tar.gz -rw------- 1 root root 4683 May 28 09:32 dead.letter drwx------ 5 root root 39 May 28 09:42 Maildir drwx------ 3 root root 21 May 27 16:27 snap |
⑨Send chkrootkit use command (compressed version) to root by e-mail
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1 |
# echo|mail -a chkrootkit_cmd.tar.gz -s chkrootkit_cmd.tar.gz root |
⑩Download and save chkrootkit_cmd.tar.gz file to Windows
⑪Delete commands on the backed up server
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1 |
# rm -f chkrootkit_cmd.tar.gz |