DroidNation podcast appearance

 

 

 

About a week or two ago I appeared on a pretty awesome podcast called DroidNation (eps 15).  DroidNation is basically the podcast for anyone that is looking to take back control of their device, from rooting to roming to overclocking you name it the got it. Every episode leaves you wanting for more. During my segment I spoke a bit about Android security, you can get the show notes here.

In short if you have not heard about  frostbite media network or DroidNation go out and add it to your podcast app  and have fun unlocking the power of your Android system.

Podcast Appearance “Attack of the Android”

Hello all, I hope your year is going well so far; I just wanted to drop a line and mention that a few weeks ago I appeared on “Attack of the Androids” podcast esp 16. A little background about the podcast, the are a weekly audio podcast focused on the Google Android operating system and community.

You can find them on Google + or follow them on twitter @aotaradio    kool cast check them out!

Notes for Linux Basix Eps20

I  appeared on the Linux Basix podcast once more, I am becoming a regular :). Below are some of the things I spoke of during my segment.

Discussion Links:

  1. Symantec Snoop Dogg rap contest site rickrolled: Symantec’s attempts to link up with Snoop Dogg to launch a cybercrime rap contest, to bring about awareness on the issue. However it turned out that the site had several vulnerabilities and had to be taken down for maintenance, read more over at  http://www.theregister.co.uk/2010/09/03/symantec_rap_contest_farce/.
  2. Facebook adds new remote log-out security feature: Facebook on Thursday announced a new security feature that will allow users to see if they are logged into their accounts on a different computer and to remotely log out if so. This can also be used to see if someone has your password and has been logging in when you are not around. The new security feature follows a Login Notification feature the company announced in May that lets users tell Facebook to notify them via e-mail or SMS when a new computer or device is used to log into their account, read more over at  http://news.cnet.com/8301-27080_3-20015482-245.html .
  3. Rosetta Stone for Unix: The goal of this site is to give you a command syntax comparison between Linux, Unix, MAC OSX, and a few others, visit http://bhami.com/rosetta.html and have some fun. Another good site with a collection of Unix/Linux/BSD commands is –> http://cb.vu/unixtoolbox.xhtml which gives you the option to save the page as a new PDF ebook.
  4. Malware hosted on Google Code project site: Malicious individuals are using the Google Code repository to host Trojans horses, backdoors and password stealing keyloggers, according to researchers at Zscaler. The researchers found a malicious project hosted on the free Google Code site with about 50+ malware executables stored in the download section of the project. “The first malicious file was uploaded on June 24, 2010 and was still active at the end of August this year, proving that Google is slow to find and remove malicious projects”, read more over at http://www.zdnet.com/blog/security/malware-hosted-on-google-code-project-site/7247

Tech Segment: Installing and using Xplico

What is Xplico?

The goal of Xplico is extract from an internet traffic capture the applications data contained. For example, from a pcap file Xplico extracts each email (POP, IMAP, and SMTP protocols), all HTTP contents, each VoIP call (SIP), FTP, TFTP, and so on. Xplico isn’t a network protocol analyzer. Xplico is an open source Network Forensic Analysis Tool (NFAT).

Features

  • Protocols supported: HTTP, SIP, IMAP, POP, SMTP, TCP, UDP, IPv6, …;
  • Port Independent Protocol Identification (PIPI) for each application protocol;
  • Multithreading;
  • Output data and information in SQLite database or Mysql database and/or files;
  • At each data reassembled by Xplico is associated a XML file that uniquely identifies the flows and the pcap containing the data reassembled;
  • Realtime elaboration (depends on the number of flows, the types of protocols and by the performance of computer -RAM, CPU, HD access time, …-);
  • TCP reassembly with ACK verification for any packet or soft ACK verification;
  • Reverse DNS lookup from DNS packages contained in the inputs files (pcap), not from external DNS server;
  • No size limit on data entry or the number of files entrance (the only limit is HD size);
  • IPv4 and IPv6 support
  • Modularity. Each Xplico component is modular. The input interface, the protocol decoder (Dissector) and the output interface (dispatcer) are all modules
  • The ability to easily create any kind of dispatcer with which to organize the data extracted in the most appropriate and useful to you

Installing and Configuring:

First begin with a little sudo fu and install the following packages:

apt-get install tcpdump tshark apache2 php5 php5-sqlite build-essential perl zlib1g-dev libpcap-dev libsqlite3-dev php5-cli libapache2-mod-php5 libx11-dev libxt-dev libxaw7-dev python-all sqlite3 recode sox lame libnet1 libnet1-dev libmysqlclient15-dev

Create a temp directory to wget your files too with mkdir Xbuild and cd Xbuild

Download Xplico source code from SorceForge or BerliOS

tar zxvf xplico-0.5.x.tgz

wget http://geolite.maxmind.com/download/geoip/api/c/GeoIP-1.4.6.tar.gz
tar zxvf GeoIP-1.4.6.tar.gz

cd GeoIP-1.4.6
./configure
make

cd ..
rm -f *.tar.gz

cd xplico
wget http://geolite.maxmind.com/download/geoip/database/GeoLiteCity.dat.gz
gzip -d GeoLiteCity.dat.gz
rm -f *dat.gz
make

cd ..
wget http://mirror.cs.wisc.edu/pub/mirrors/ghost/GPL/ghostpdl/ghostpdl-8.70.tar.bz2
tar jxvf ghostpdl-8.70.tar.bz2

The ghostpcl contains the pcl6 application that it is necessary to “network printer job”

rm -f *.bz2
cd ghostpdl-8.70
make

Wait for some time

cd ..
cp ghostpdl-8.70/main/obj/pcl6 xplico-0.5.x
rm -rf ghostpdl-8.70

Download videosnarf from http://ucsniff.sourceforge.net/videosnarf.html. Note for 64 bits architectures: Some codec libraries are proprietary and are only for 32bits architecture. The only solution in this case is this: http://forum.xplico.org/viewtopic.php?p=453#p453

wget http://downloads.sourceforge.net/project/ucsniff/videosnarf/videosnarf-0.63.tar.gz
tar xvzf videosnarf-0.63.tar.gz
cd videosnarf-0.63
./configure
make
cd ..
cp videosnarf-0.63/src/videosnarf xplico-0.5.x

Install Xplico

cd xplico-0.5.x
make install

Copy Apache configuration file

cp /opt/xplico/cfg/apache_xi /etc/apache2/sites-enabled/xplico

After this we have to change Apache ports file to add port of XI. Then, in /etc/apache2/ports.conf add:

# xplico Host port
NameVirtualHost *:9876
Listen 9876

We must also modify the php.ini file to allow uploads (pcap) files. Edit /etc/php5/apache2/php.ini.

The lines to modify are:\
**post_max_size = 100M** \
**upload_max_filesize = 100M**\

Enable mode rewrite in Apache:

a2enmod rewrite

And finally restart Apache:

/etc/init.d/apache2 restart

You can find much more information and documentation on the wiki –> http://wiki.xplico.org.

Uploading your first PCAP file:

  1. Log into the user inter by going to http://xplicoip:9876
  2. Username:xplico and password:xplico please change after
  3. Click on Case to create a new case.
  4. Click on session to create a new session
  5. Click on newly created session within the newly created case and click upload–> browse to your capturefile.pcap.
  6. You can also create a live stream and just have the host sit there passively listening.

Sit back wait for xplico to works it’s magic and then browse your results. View this page to see screen-shots of all the various options of xplico –> http://wiki.xplico.org/doku.php?id=web_interface. Now all your have to do is go sniffing, read the manual and have fun viewing your results.

Linux Basix Security Tips Part 1

A while back I hinted to the wonderful guys over at  http://www.linuxbasix.com/ that I would like to appear on the show and do a segment on Linux security, the agreed and below are some of the notes that can be used to follow alone with my segment.

Disclaimer: I am by no means a Linux security expert; I am just trying to bring some visibility to a topic that I believe all new users should think about.

Taken from the Linux basix website, our goal here is to bring together information that will make your introduction to Linux and Open Source Software more enjoyable and productive. As we go along we will be constantly updating this site with our shows and show notes. If you have any questions please post comments to the shows and blog. Feel free to let us know what you think of the show and we will do our best to make it make as much sense as possible. Once the forum is up and running it will be a source to find answers, tips and tricks to make computing more enjoyable.

The goal of my segment is not to touch on anything too advance, for that you can find several Linux hardening guide by CERT, NSA, and many more resources out there. Instead I will be focusing on giving a few tips that anyone new to Linux should keep in mind before connecting their server/workstation to the internet.

I would like to start by sharing a few sentences I found in a blog posting over at computer world;

“You see Windows was designed as a single-user, non-networked operating system. That design is still at the heart of Windows, which is why security must always be an add-on to Windows. Linux, in contrast, was built from the ground up as a multi-user, networked system. Linux, like Unix, which came before it, was constructed to work in a world with hostile users.”

Physical Security ( might seem silly but this should always be considered)

Configure the BIOS to disable booting from CDs/DVDs, external devices, and set a password to protect these settings, you can also go another step by encrypting your entire drive. Next, set a password for the GRUB bootloader.

  • Generate a password hash using the command  /usr/sbin/grub-md5-crypt.
  • Add the hash to the first line of /boot/grub/menu.lst as follows: password –md5 passwordhash

Minimum install as possible

Take a moment to think about your installation, I understand you might not know exactly what you want but don’t install everything at first. Just do the basics and as you learn more you can then install those additional application and do it properly. Also remove unnecessary packages, only keep the ones you need, and lastly remove any accounts that are not needed.

# yum list installed
# yum list packageName
# yum remove packageName

OR

# dpkg –list
# dpkg –info packageName
# apt-get remove packageName

Stay away form clear text protocols

Under no circumstances do you want to use any clear text protocol. Any of the following  protocols or programs   (telnet, rsh, rlogin, FTP, TFTP) can give out your username/password to anyone on your local network with a packet sniffer. If you are hosting a website or providing users with a login portal ensure that you are not using http, but instead https even if you have to generate your own certificate.

Identify all open ports and services

Its important to know what ports you have open and what services are associated to them this way you can decide if you would like to block or filter them with a firewall. This is also important so in the event you notice a new port open you already have a baseline to compare it too.

To do you can use a tool like  Nmap (“Network Mapper”) which is a free and open source (license) utility for network exploration or security auditing. Many systems and network administrators also find it useful for tasks such as network inventory, managing service upgrade schedules, and monitoring host or service uptime.

ex nmap -A -sV 127.0.0.1

You can also use the following for identifying and turning off unwanted services:

To view all services that are turned on:
# chkconfig --list | grep '3:on'

To disable a service:

# service serviceName stop
# chkconfig serviceName off

Security software

  • Install Antivirus software, I am aware that Linux is not highly prone to viruses like your average Windows PC, but don’t for a moment think that Linux is not being successfully exploited in the wild every day. You want to ensure that you are not the “Low Hanging Fruit” in short don’t be the easy target.
  • Install/configure firewall (SELinux, IP Tables, and AppArmor) and take a moment to read how to configure it.

Keep Your Software Up to Date

  • Configure your system to update via your software repository and apply then automatically. Security updates should be applied as soon as possible.
  • Create the file apt.cron, make it executable, place it in /etc/cron.daily or /etc/cron.weekly, and ensure that it reads as follows:

#!/bin/sh
/usr/bin/apt-get update
#
Or aptitude –s safe-upgrade

Password policy

  • You want to insure that you have a proper password policy, first identify any user accounts that has an empty password and set on or remove the account.
  • Setup password aging, its important to keep rotating your password a minimum every 60 days.
  • Set up some sort of password lockout policy, if someone attempts a brute force attempt you need to at least slow them down, a standard practice is to lockout an account after 3 failed login attempts.To get password expiration information, enter:
    chage -l userName

    To see failed login attempts, enter:
    faillog

    To unlock an account after login failures, run:
    faillog -r -u userName

    Note you can use passwd command to lock and unlock accounts:
    # lock account
    passwd -l userName

    # unlock account
    passwd -u userName

    Identify empty passwords type the following command
    # awk -F: ‘($2 == “”) {print}’ /etc/shadow

Make Sure No Non-Root Accounts Have UID Set To 0

Only root account have UID 0 with full permissions to access the system. Type the following command to display all accounts with UID set to 0:

# awk -F: '($3 == "0") {print}' /etc/passwd

You should only see one line as follows:
root:x:0:0:root:/root:/bin/bash

If you see other lines, delete them or make sure other accounts are authorized by you to use UID 0.

File and file system security

SUID and SGID files on your system are a potential security risk, and should be monitored closely. Because these programs grant special privileges to the user who is executing them, it is necessary to ensure that insecure programs are not installed. A favorite trick of crackers is to exploit SUID-root programs, then leave a SUID program as a back door to get in the next time, even if the original hole is plugged.

  • Find all SUID/SGID programs on your system, and keep track of what they are, so you are aware of any changes which could indicate a potential intruder. Use the following command to find all SUID/SGID programs on your system:

root# find  / -type  f ( -perm -04000 -o -perm -02000 )

World-writable files, particularly system files, can be a security hole if a cracker gains access to your system and modifies them. Additionally, world-writable directories are dangerous, since they allow a cracker to add or delete files as he wishes. (can upload malware to a site and infect visitors)

To locate all world-writable files on your system, use the following command:

find / -xdev -type d ( -perm -0002 -a ! -perm -1000 ) -print

Secure ssh remote access

  • Disable root login via ssh, if someone is going to try and brute force your ssh server the first user name the will try will be root, so ensure that you do not allow ssh login for your root user. You can verify or edit this but changing the config file in:

vi /etc/ssh/sshd_config

Find this section in the file, containing the line with “PermitRootLogin” in it.

#LoginGraceTime 2m
#PermitRootLogin no
#StrictModes yes
#MaxAuthTries 6

Then restart your SSH service with sudo /etc/init.d/sshd restart

Noowner Files

Files not owned by any user or group can pose a security problem. Just find them with the following command which do not belong to a valid user and a valid group.

find /dir -xdev ( -nouser -o -nogroup ) -print

Keeping an eye on your logs:

You should configure logging and auditing so you can keep an eye on any type of  attacks that are launched against your system. You can manually check the following logs or use a tool like logwatch or logcheck or any number of log parsers out there. Logs of interest are :

  • /var/log/syslog
  • /var/log/faillog
  • /var/log/auth
  • /var/log/lastlog
  • /var/log/messages
  • /var/log/apahe2/access.log and error.log

When all else fail, here are some useful Scripts and tools you can use:

Lynis: Lynis is an auditing tool for Unix (specialists). It scans the system and available software, to detect security issues. Beside security related information it will also scan for general system information, installed packages and configuration mistakes.

Security audit tool,is a security tool that can be used both as a security audit as well as a part of an intrusion detection system. It consists of set of tests, library and textual/graphical front-end. Tests are sorted into groups and security levels. Administrators can run selected tests, groups or whole security levels.

The Bastille Hardening program “locks down” an operating system, proactively configuring the system for increased security and decreasing its susceptibility to compromise. Bastille can also assess a system’s current state of hardening, granularity reporting on each of the security settings with which it works.

audit2.pl (perl): This second script searches the entire file system, listing SUID, SGID, world-writable, group-writable files. It also lists trust files and their contents. Finally it lists files with weird names (e.g., containing punctuation characters), which might be danger or a sign of penetration. On a large server with 100GB disks, this can take a few hours to run.

Unix-privesc-checker is a script that runs on Unix systems (tested on Solaris 9, HPUX 11, Various Linuxes, FreeBSD 6.2).  It tries to find misconfiguration that could allow local unprivileged users to escalate privileges to other users or to access local apps (e.g. databases).

DenyHosts is a script intended to be run by Linux system administrators to help thwart SSH server attacks (also known as dictionary based attacks and brute force attacks).

OpenVAS stands for Open Vulnerability Assessment System and is a network security scanner with associated tools like a graphical user front-end. The core component is a server with a set of network vulnerability tests (NVTs) to detect security problems in remote systems and applications.

References:

http://iase.disa.mil/stigs/checklist/index.html

http://www.sans.org/score/checklists/linuxchecklist.pdf

http://www.nsa.gov/ia/_files/os/redhat/rhel5-guide-i731.pdf

http://georgia.ubuntuforums.org/showthread.php?t=1002167&page=2

http://boilinglinux.blogspot.com/2008/07/ubuntu-hardy-hardening.html

http://www.cyberciti.biz/tips/linux-security.html

http://www.debian.org/doc/manuals/securing-debian-howto/

http://tldp.org/HOWTO/Security-HOWTO/file-security.html

http://blogs.computerworld.com/16367/dell_back_tracks_on_linux_being_safer_than_windows

http://www.rootkit.nl/projects/lynis.html

https://fedorahosted.org/sectool/

http://www.security-database.com/toolswatch/

http://securitytube.net/Mastering-IPTables-video.aspx

http://nmap.org/

http://www.openvas.org/

http://www.bastille-unix.org/

http://denyhosts.sourceforge.net/

http://pentestmonkey.net/tools/unix-privesc-check/

http://www.boran.ch/audit

http://oreilly.com/pub/h/66

http://www.howtogeek.com/howto/linux/security-tip-disable-root-ssh-login-on-linux/

http://www.cyberciti.biz/faq/linux-log-files-location-and-how-do-i-view-logs-files/