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361  Resources / News from the Outside World / Re: Tomorrow should be a holiday on: February 13, 2009, 06:04:19 AM
I just came from College, so it wasn't a holiday for me Grin
362  Ethical Hacking Discussions and Related Certifications / Network Pen Testing / Re: An Ethical Hacker must have these skills... on: February 13, 2009, 05:21:20 AM
You can start by getting a basic understanding of metasploit by reading the user guide that comes along with it.
www.metasploit.com/documents/users_guide.pdf

After this you can proceed to other books.
http://books.google.com/books?q=metasploit

I'm currently reading Metasploit Toolkit for Penetration Testing, Exploit Development, and Vulnerability research and am happy with it.
363  Ethical Hacking Discussions and Related Certifications / Incident Response / Re: What are your recommendations for Incident Response books? on: February 13, 2009, 04:35:02 AM
Hello unsupported!

The links by Jhaddix and Jason pretty much covers it all and I think would be sufficient to help you get a good grasp of the subject.
In case you want  some reviews of the books you should go for I suggest reading this article by Tony Bradley. Perhaps these would be enough to give you a nice start.
364  Ethical Hacking Discussions and Related Certifications / Malware / Re: Want to make $250,000 the easy way? on: February 13, 2009, 04:10:35 AM
Here's the complete article.
http://news.cnet.com/8301-1009_3-10163084-83.html
365  Ethical Hacking Discussions and Related Certifications / Malware / Re: ANTIVIRUS-Yes or No? on: February 12, 2009, 07:38:40 AM
do you recommend use any antivirus  if you use linux at home?

this post is for all O.S and just for windows?
I would definitely go for an antivirus even with Linux too. Linux though has small no. of viruses dedicated to it but it's still useful to have some antivirus scanners and run it just for once every week or fortnight.
Avast has a Linux version too but just as sgt_mjc said I would go with Clam AV with ubuntu.
366  Resources / Tutorials / Nmap Scans:Part 2 on: February 10, 2009, 11:08:48 PM
If you are reading this tutorial then you must have obviously read my previous tutorial on Nmap scans. If not then read it here.

B: TCP Connect() Scan
Remember the three-way handshake?I hope you do.
TCP Connet() Scan is just the normal three way handshake.

1: Firstly Nmap sends a SYN packet to the destination port.
2: The destination post -if open- replies with a SYN-ACK packet.
3: Now Nmap replies with a normal ACK packet and establishes the connection.
4: But soon after establishing the connection Nmap sends a RST packet and breaks the connection.

The steps explained above were for open ports. In case of closed ports:
1:Firstly Nmap sends a SYN packet to the destination port.
2:The remote port -since it's closed- sends a RST response.

       Nmap ------------------>SYN------------------->Remote port

       Nmap<----------------SYN-ACK<----------------Remote port

       Nmap------------------->ACK------------------->Remote port

       Nmap------------------->RST------------------->Remote port

                                  OPEN PORT




      Nmap ------------------>SYN---------------->Remote port

       Nmap<-------------------RST<----------------Remote port

                                 CLOSED PORT

Sometimes it happens that Nmap sends a SYN packet to the remote port and gets no response. It means that a firewall is blocking the packet. Nmap declares these posts as filtered

       Nmap ------------------>SYN---------------->Remote port

       Nmap---------------NO RESPONSE-------------Remote port

                               FILTERED PORTS

TCP connect() scan is the default scan if you are running as a privileged user.

The syntax for TCP connect() scan in CLI is:
nmap -sT remote I.P

Here -sT is the command for TCP connect() scan and remote I.P is the I.P address of the target machine you want to scan.




C: IDLE Scan

Idle scan depends on a Zombie and IPID no.

Zombie

Zombie is an idle station that acts as an intermediate between the Nmap station and the target I.P address. The zombie station should remain idle during the duration of the scan to maintain consistency in the IPID no.
The other thing to note about zombie is that it could be any device from an idle server, a workstation or a printer.

IPID
Fyodor very briefly explained the IPID no. and I just use his definition:
Every IP packet on the Internet has a fragment identification number (IP ID).  Since many operating systems simply increment this number for each packet they send, probing for the IPID can tell an attacker how many packets have been sent since the last probe.

IDLE Scan steps
Now back again to our three way handshake.
Suppose computer A instead of sending a SYN packet to computer B sends a SYN-ACK. When computer B receives this unsolicited SYN-ACK it responds with a RST packet. This concept is very cleverly used in IDLE Scan.

1: Firstly Nmap station sends a SYN0ACK packet to the zombie. Thsi unsolicited SYN-ACK is responded with a RST packet. Nmap then notes the IPID no of this RST packet.

2: Nmap then spoofs the I.P add. of the zombie and sends a SYN packet to the target device.:
  a: If the port is open it sends a SYN-ACK response to the zombie. Zombie on receiving the unsolicited SYN-ACK responds with a RST.

  b: If the port is closed then target device responds with a RST packet to the zombie. Zombie  discards the unsolicited RST.

3: Nmap the again sends a SYN-ACK to the zombie and receives
    a: In case of open ports the IPID of zombie increments by two because zombie sent two paket--one RST to the target device in response to SYN-ACK from it and another RST to the Nmap statio.

    b: In case of closed ports the IPID of zombie increments only by one because zombie sent only one RST packet to the Nmap station.

 Nmap station-------------------->SYN-ACK---------------------------->Zombie
 Nmap station<------------------RST (IPID=25)<------------------------ Zombie


Nmap station-------------------->SYN--------------------------->Target device
(Spoofed Zombie's
 I.P add.)


 Zombie<---------------------------SYN-ACK<---------------------Target device
 Zombie------------------------->RST (IPID=26)----------------->Target device

                                            OPEN PORT


Zombie<-----------------------------RST<--------------------------Target device

                                                   CLOSED PORT


IDLE Scan is a very stealth scan. It's very difficult to trace the attacker in this scan.

Syntax of IDLE Scan for CLI is:
nmap  -P0 -sI  I.P add. of zombie  I.P add. of target device.

The -P0 option tells Nmap not to ping the target device otherwise target device could trace the attacker from the ping packets.
-sI  is the idle scan command.
367  Resources / Tutorials / Re: Nmap Scans: Part 1 on: February 10, 2009, 06:52:22 AM
Quote
nice, i am goint to install BACK TRACK after that  i will try this tutorial
There' a windows version of Nmap too.

just a question, where do u work men?


I'm a second year computer science engineering student.
368  Ethical Hacking Discussions and Related Certifications / Malware / Re: ANTIVIRUS-Yes or No? on: February 09, 2009, 04:24:51 AM
A good read Stifler Smiley
Nice you explained all of these tools and also gave warnings regarding some (Hijackthis). Hijackthis is definitely not a tool for beginners. You should have a proper training to use this tool and I gave the link of ASAP websites which provide free training.
I see that you are using Threatfire. It's an excellent tool and I have also used it for about an year but it takes a lot of system resources and makea the computer slow. Perhaps that's the problem with you too.
Keyscrambler is good and I have tried it. The free version of malwarebytes is also good and I have it on my system.(Didn't feel like buying it Wink)
However I would just like to advice you not to use two firewalls( I see you are running both Zonealarm and Blackice). Just having any one of them is enough for your system.
Besides that I also got to know about some tools I didn't know before. Grin

Thanks
369  Resources / Tutorials / Nmap Scans: Part 1 on: February 09, 2009, 04:08:49 AM
In this tutorial I'll teach you some basic Nmap scans.

Before learning about the scan methods you should have a basic understanding of TCP and UDP. So I'll also cover these topics very briefly.

UDP

UDP stands  for User Datagram Protocol.
UDP is a connectionless protocol i.e packets are sent from one party to another without any prior connection establishment between the two. This method of transmission doesn't guarantee that the data will reach it's destination. The packets may be delayed, arrive out of sequence or lost.
Thus we can say that UDP isn't a reliable protocol.

TCP
TCP stands for Transmission Control Protocol.
TCP is a connection oriented protocol i.e data exchange occurs between the sender and the receiver only after a connection is established between the two.
Connection is established using three way handshake.

To understand the three way handshake you have to know about the flags field in a TCP header.

Flags field or control field is a 6 bit field and is used to relay control information between TCP peers.
The various types of flags are:
A: SYN or synchronize flag is used to synchronize the sequence numbers.

B:FIN or finish is used to tell the remote machine to terminate the connection.

C:ACK or acknowledgment is the acknowledgment field significant.

D:PSH or push flag is a notification from the sender to the receiver to pass all the data the receiver has to the receiving application.

E:URG or urgent flag signifies that the packet contains urgent data.

F:RST or reset flag is used to reset the connection.

With the knowledge of flags under our belt we can proceed to learn Three -way handshake.

Suppose computer A wants to establish a connection with computer B.
1:Firstly, computer A sends a packet with SYN flag set to computer B
2:Computer B after receiving the SYN packet sends packet with SYN-ACK flag  set to computer A.
3:When computer A receives the SYN-ACK packet it sends a packet with ACK flag set to computer B.
4:Finally, when computer B receives the ACK packet the connection is established.

Computer A --------------------->SYN------------------->Computer B

Computer A<-------------------SYN-ACK<-------------------Computer B

Computer B---------------------->ACK------------------->Computer B



Let's now discuss the Nmap scan methods.

The first scan we'll be talking about is the SYN Scan or sometimes called the half-open scan

A: SYN Scan

SYN scan or half-open scan is almost like the three-way handshake except for one step.
1: Firstly Nmap sends a SYN packet to the destination port.
2: The destination post -if open- replies with a SYN-ACK packet.
3: Now Nmap doesn't wants to establish a connection and instead of sending an ACK response sends a packet with RST flag, and this is where it deviates from the normal three-way handshake.

The steps explained above were for open ports. In case of closed ports:
1:Firstly Nmap sends a SYN packet to the destination port.
2:The remote port -since it's closed- sends a RST response.

Nmap ------------------>SYN------------------->Remote port

Nmap<----------------SYN-ACK<----------------Remote port

Nmap------------------->RST------------------->Remote port

                            OPEN PORT



Nmap ------------------>SYN---------------->Remote port

Nmap<-------------------RST<----------------Remote port

                           CLOSED PORT


Sometimes it happens that Nmap sends a SYN packet to the remote port and gets no response. It means that a firewall is blocking the packet. Nmap declares these posts as filtered

Nmap ------------------>SYN---------------->Remote port

Nmap---------------NO RESPONSE-------------Remote port

                        FILTERED PORTS



SYN scan is the default scan if you are running as a privileged user

The syntax to run this scan in CLI is:
nmap -sS Remote I.P

Here -sS is the SYN scan command and the remote I.P is the I.P address that you want to scan.

So the command looks like this:

You must be asking that if SYN scan is the default scan then for privileged users then why is it necessary to specify the SYN scan command? Well, it isn't. The scan will work perfectly by just using the command: 
nmap remote I.P

But it's a good practice to specify this command in case you are'nt running privileged in which case TCP connect() scan is the default scan.

That's it for this part. I'll be taking more scans in the other parts of this tutorial.
370  Resources / Tutorials / Password Protection on: February 07, 2009, 04:46:50 AM
This guide is aimed at absolute beginners. If you are a pro then you'll not be benefiting much from it. However that shouldn't prevent you from reading it.Perhaps you may get to learn something new.

Password security is one of the main concern of computer users. People use passwords for everything from logging in to the computer, using e-mails, online bank accounts and accessing forums Cheesy

A simple username-password is one of the most common schemes of authentication i.e they help to verify your identity. It's such a simple scheme that every computer user is prone to identity theft i.e if someone gets hold of yor password then they can easily access your accounts.

In this document I'll try to teach you some methods to make strong and secure passwords.
While teaching methods to effectively secure your passwords I'll also try to discuss some(read, not all) methods of how they are cracked/stolen.

Passwords can be of the following types:-
1: All letters
2: All numbers
3: All special characters
4: Combination of letters and numbers
5: Combination of numbers and special characters
6: Combination of letters and special characters
7: Combination of letters, numbers and special characters.
8: Another category which actually is the sub-category of letters and used in this forum is using a combination of uppercase and lowercase letters along with numbers and special characters.

The most common ways in which passwords can be stolen are:-
A: Dictionary attack
B: Brute force attack
C: Hybrid attack
D: Password guessing
E: Keylogging

PASSWORD GUESSING
password guessing is simply when an attacker tries to guess your password. Most of the users make the mistake of using their D.O.B, their family members' name, their phone no. or other personal info. as passwords. Attacker knows all of this and tries to guess your password. It seems easy but is very effective in case of weak passwords.

DICTIONARY ATTACK

Dictionary Attack uses a dictionary. Password Crackers will try every word from the dictionary as a password. A good dictionary (also known as a word list) is more than just a dictionary, e.g. you will not find the word "qwerty" in the ordinary dictionary but it will surely be included into a good word list. Indeed, this combination of characters is commonly used as a password.
(Definition borrowed from lastbit.com)

BRUTE FORCE ATTACK

Brute Force Attack is the most widely known password cracking method. This attack simply tries to use every possible character combination as a password. To recover a one-character password it is enough to try 26 combinations (‘a’ to ‘z’).
(Definition borrowed from lastbit.com)

HYBRID ATTACK
In this case, the password cracker checks all words in the dictionary along with its variations. These can be, for example, the same words with different digits appended to them.
(Definition borrowed from lastbit.com)

KEYLOGGING
Key logger is a software or a hardware that records every keystroke that a user types on his keyboard.

This is a good link if you want to learn about the common password cracking methods.
http://lastbit.com/password-recovery-methods.asp

Now let's discuss some methods of securing your passwords:-
A: Never use personal info. like you name, D.O.B etc as passwords.Attacker knows all of this and password guessing is usually the first step he would perform. Furthermore, a simple name can be easily brute forced.

B: Never use common words like starwars, dexter etc. as your passwords. Dictionaries in the dictionary attack are wiser than you think

C: A good password should be a combination of letters, no. and special characters. You can go ahead with a combination of uppercase and lowercase letters, no. and special characters. This makes it very difficult to bruteforce. To give you an idea of how much time it takes to brute force a password read this:
http://lastbit.com/rm_bruteforce.asp

D:  good password should have at least 8 characters to make it very difficult to brute force as you read above.

E: To protect yourself from keyloggers read my guide on how to protect your computer(I'll be posting it in some days). You can go ahead and use an anti-keyloggers.
ZEMANA ANTILOGGER is a good anti-keylogger

F: Make a policy to change your passwords regularly-like every fortnight or every month. This gives less time to the attacker to crack your passwords.

G: Some people often make the mistake of keeping their passwords written in random papers and leave it on their desk etc. Never do this. Anyone can get hold of your passwords and access your acconts.

There are several tested ways to make secure passwords. I discuss some of them here.
A: Phrase alter rule
I just came up with this name to explain you. So you won't be hearing this rule name anywhere else but you would be stumbling upon this method very often.
Suppose you took the first two lines of the Christmas song or any other sng you want(Enrique's my favorite Wink)

Jingle Bell Jingle Bell Jingle All The Way

Carry the first letters of each word and write it in capital

JBJBJATW


Now alter every second letter to small letters.

JbJbJaTw

Now use 6 for every b and @ for a

Therefore your new password is:

J6J6@Tw


Simple isn't it?

B: Phrase alter plus rule
This is just my modified version of phrase alter rule.
Instead of using songs I use a common word and the application name for which I want to use my password.
So suppose I want to make a password for linux. I would use my username(Xen in this case)and Linux and come up with a string:

XEN_LINUX


This string already has a special character( _ ) but that's not enough. I'll again alter every second letter to smaller case.

XeN_lInUx

Now every vowel is changed to @ and any one of the letter converted to a number (In this case I change l to 1)
Therefore the new password is:

XeN_1@n@x


This is nothing but an eg. to give you an idea how you can change the Phrase Alter Rule to suit your own needs.

C:Long phrase rule

It's the easiest rule.No special characters or numbers required. All you have to do is use a very long phrase as your password.
So I choose:
When in rome do as the romans do

The length of the string makes it very difficult to crack and it's very easy to remember.
371  Features / Opinions / Re: Is Professer Messer's Nmap Training Course worth doing? on: February 07, 2009, 03:59:03 AM
I have taken the course and it IS good, but nothing compared to Fydors book.

Maybe i can post an official review of Professor Messor's training soon =)
I guess I should read the book then.
Thanks both of you. (Should I say love ya ?Cheesy)
372  Ethical Hacking Discussions and Related Certifications / Wireless / Re: When is enough really enough? on: February 07, 2009, 02:56:53 AM
A good question raised. But I don't think that people completely neglect their security. They are oblivious of the methods in which their security can be breached.
You and I being in this field know that WEP can be cracked but for an average computer user he has put his security measures in place.
For learning security measures you have to learn how security is cracked too.And this is where the difference comes in. We can't develop interest in the average computer user for computer security. At best what we can do is guide them or posts some stuff keeping average users in mind too.
373  Features / Opinions / Is Professer Messer's Nmap Training Course worth doing? on: February 07, 2009, 02:05:26 AM
Some time back I stumbled upon this course and though the website captivated me I have still not make up my mind whether to go ahead with the course.
I think I know a lot about Nmap with the basics of every scan it performs but there's always a chance to learn more.
Would anyone who took this course guide me whether or not to go ahead?
http://www.professormesser.com/nmap-secrets-training-course
374  Resources / Links to cool sites. / Port Scanning with Nmap on: February 06, 2009, 02:50:34 AM
A good tutorial about Nmap scans
http://www.petri.co.il/port-scanning-with-nmap.htm
375  Resources / Links to cool sites. / Re: Some people search websites on: February 06, 2009, 01:15:40 AM
Nice! Thanks Don and Kris
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