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Thursday 30 June 2011

HTTP and HTTPS: The Hacking Protocols




Introduction
On the Internet billions of electrons pass along thousands of miles of cable every day to and from destinations around the world and beyond. These electrons carry written messages, visual images, and sound between millions of computers connected to the World Wide Web. Many of the transmissions contain vital and confidential information that can be used for mischief and fraud by hackers if they gain access to them—and many do. How can they still get in, with so much technological progress in firewalls and intrusion detection software? The answer is two numbers: TCP ports 80 and 443.

HyperText Transfer Protocol (HTTP) and HTTP over SSL (HTTPS), which are run through those ports, respectively, account for a growing number of cyber break-ins. Why? The reason is simple: People have fallen for the biggest scam going. The ruse is shamelessly perpetuated throughout the industry by software vendors and service providers alike. As they state confidently, "Purchase a good firewall and intrusion detection system (IDS) and your security problems will melt away." Anyone with a double digit I.Q. should know that, no matter how many firewalls and IDS systems you have, they will never prevent Web attacks.



Firewalls are useless against Web attacks. That's right. Firewalls are pebble speed bumps in the residential street of the Internet. Why? Because firewalls have to let Web traffic through them. As a result, HTTP/HTTPS leave an attacker almost immune from the effects of firewalls. HTTP is truly a hacker's delight. And whatever can be done over HTTP can usually be done over HTTPS in the encrypted stream of anonymity. In this chapter we discuss both protocols (HTTP and HTTPS), describe how they work, and suggest ways that attackers extend their boundaries.



Protocols of the Web

The World Wide Web is an array of protocols that act like traffic cops for the Internet. Packets can be thought of as cars, trucks, and buses on the information superhighway with protocols being stop signs, traffic lights, and drawbridges. So, by their very definition, protocols play a crucial role in managing the day-to-day activities on the Internet. As a result, they are especially important to hackers who want to take advantage of their flaws (and sometimes their features).

In this chapter we discuss the major protocols of e-commerce and how hackers attempt to alter them for their own gain. We also describe a number of free tools that take advantage of these protocols, automating much of the heavy lifting.

HTTP
Without a doubt, HTTP is the most ubiquitous protocol in use on the Internet. Every Web browser and server must communicate over this protocol in order to exchange information. There have been three major versions of the protocol, all of which maintained the same fundamental structure. HTTP is a request/response stateless protocol that allows computers to talk to each other rather efficiently and carry on conversations lasting hours, days, and weeks at a time.

Although the HTTP/1.0 specification currently in use is a far cry from the original specification proposed by Tim Berners-Lee in March 1990, the fundamental features of HTTP haven't changed all that much. Figure 4-1 highlights the major components of the HTTP protocol and their use.




HTTP/0.9The first official HTTP specification is typically considered HTTP/0.9. This version and its successor are defined in the Internet Engineering Task Force's (IETF) Request for Comments (RFC) document RFC1945 (http://www.ietf.org/rfc/rfc1945.txt). For four years (1992–1996), HTTP/0.9 found modest use on the Internet despite the Web's infancy at the time. HTTP/0.9 was limited in many ways and didn't cover what we now consider to be required elements of Web interaction.


HTTP/1.0

The HTTP/1.0 specification came along just as the Internet started to heat up. Despite its relative age in the technological sense—it was finalized in May 1996—HTTP/1.0 remains the king of the HTTP protocol versions on the Internet. Most Web servers and browsers still use HTTP/1.0 for default communication. As with HTTP/0.9, HTTP/1.0 is covered under RFC 1945.

The underpinnings of the HTTP/1.0 protocol reside with the request/response exchange. This exchange permits information to be sent, parsed, and returned between a client (Web browser) and a server (Web server)—or prevents it.

In general, the HTTP/1.0 URL looks something like this:

http://host [ ":" port ] [ absolute_path ]
The host is the hostname desired, the port is the place to put an optional port number, and absolute_path is the resource requested.


HTTP Response


An HTTP request from a client is handled by the server and responded to accordingly. To respond, the server sends back a series of message components that can be categorized as follows:

· Response code—a numeric code that corresponds to an associated response.

· Header fields—additional information about the response.

· Data—the content or body of the response.

With these three components, the client browser understands the server's response and interacts with the server. Now let's examine each component a little more closely.



Header Fields


The data portion of the client's request or the server's response is really the body of the communication between the two. In the case of a GET method request for the default resource, you would perform the following:

C:\> nc.exe www.example.com 80
GET / HTTP/1.0
Another here
and the default Web page (data or body) would be sent back in a stream.



HTTP/1.1


Released as an official specification in 2001, HTTP/1.1 is the latest incarnation of the HTTP protocol and is widely used. The IETF's RFC 2616 details the particulars of this latest version and highlights the additional functionality from HTTP/1.0. The primary failings of HTTP/1.0, and therefore the need for 1.1, include no hierarchical proxy support, little support for caching, and no proper handling of persistent connections and virtual hosts.

The HTTP/1.1 URL looks like this:

http://host [ ":" port] [ absolute_path [ "?" query ]]



HTTP Response


As in HTTP/1.0 responses, HTTP/1.1 requests from a client are handled by the server and responded to accordingly. HTTP/1.1 can be categorized as follows:

· Response Code—a numeric code that corresponds to an associated response.

· Header fields—additional information about the response.

· Data—the content or body of the response



Response Codes


The HTTP/1.1 specification added numerous response codes to the list, but the heart of the response codes didn't change. So, to understand the specifics of the HTTP/1.1 response codes, be sure to refer to the HTTP/1.0 protocol discussed earlier.



The easiest way to watch SSL work is with a network packet analyzer. Using Snort (http://www.snort.org), you can observe how traffic over TCP port 80 can be seen and recorded:



04/14-22:43:39.781452 192.168.0.5:80 -> 192.168.0.3:2590
TCP TTL:128 TOS:0x0 ID:18197 IpLen:20 DgmLen:344 DF
***AP*** Seq: 0x22AA9B72 Ack: 0xFDC79BB8 Win: 0x445F TcpLen: 20
0x0000: 00 06 5B 30 04 0C 00 20 78 0D 1F 4C 08 00 45 00 ..[0... x..L..E.
0x0010: 01 58 47 15 40 00 80 06 31 32 C0 A8 00 05 C0 A8 .XG.@...12......
0x0020: 00 03 00 50 0A 1E 22 AA 9B 72 FD C7 9B B8 50 18 ...P.."..r....P.
0x0030: 44 5F 33 9A 00 00 48 54 54 50 2F 31 2E 31 20 32 D_3...HTTP/1.1 2
0x0040: 30 30 20 4F 4B 0D 0A 44 61 74 65 3A 20 4D 6F 6E 00 OK..Date: Mon
0x0050: 2C 20 31 35 20 41 70 72 20 32 30 30 32 20 30 36 , 15 Apr 2002 06
0x0060: 3A 31 31 3A 35 33 20 47 4D 54 0D 0A 53 65 72 76 :11:53 GMT..Serv
0x0070: 65 72 3A 20 41 70 61 63 68 65 2F 31 2E 33 2E 31 er: Apache/1.3.1
0x0080: 32 20 28 57 69 6E 33 32 29 20 41 70 61 63 68 65 2 (Win32) Apache
0x0090: 4A 53 65 72 76 2F 31 2E 31 20 6D 6F 64 5F 73 73 JServ/1.1 mod_ss
0x00A0: 6C 2F 32 2E 36 2E 34 20 4F 70 65 6E 53 53 4C 2F l/2.6.4 OpenSSL/
0x00B0: 30 2E 39 2E 35 61 20 6D 6F 64 5F 70 65 72 6C 2F 0.9.5a mod_perl/
0x00C0: 31 2E 32 32 0D 0A 4C 61 73 74 2D 4D 6F 64 69 66 1.22..Last-Modif
0x00D0: 69 65 64 3A 20 4D 6F 6E 2C 20 30 38 20 41 70 72 ied: Mon, 08 Apr
0x00E0: 20 32 30 30 32 20 30 31 3A 33 34 3A 35 35 20 47 2002 01:34:55 G
0x00F0: 4D 54 0D 0A 45 54 61 67 3A 20 22 30 2D 38 34 62 MT..ETag: "0-84b
0x0100: 2D 33 63 62 30 66 33 62 66 22 0D 0A 41 63 63 65 -3cb0f3bf"..Acce
0x0110: 70 74 2D 52 61 6E 67 65 73 3A 20 62 79 74 65 73 pt-Ranges: bytes
0x0120: 0D 0A 43 6F 6E 74 65 6E 74 2D 4C 65 6E 67 74 68 ..Content-Length
0x0130: 3A 20 32 31 32 33 0D 0A 43 6F 6E 6E 65 63 74 69 : 2123..Connecti
0x0140: 6F 6E 3A 20 63 6C 6F 73 65 0D 0A 43 6F 6E 74 65 on: close..Conte
0x0150: 6E 74 2D 54 79 70 65 3A 20 74 65 78 74 2F 68 74 nt-Type: text/ht
0x0160: 6D 6C 0D 0A 0D 0A



The packet being returned from the server displays the normal output to a HEAD request of the server. Now let's look at the same packet running over SSL:


04/14-22:46:51.135042 192.168.0.5:443 -> 192.168.0.3:2592
TCP TTL:128 TOS:0x0 ID:18212 IpLen:20 DgmLen:339 DF
***AP*** Seq: 0x25992D24 Ack: 0xB641BA Win: 0x4266 TcpLen: 20
0x0000: 00 06 5B 30 04 0C 00 20 78 0D 1F 4C 08 00 45 00 ..[0... x..L..E.
0x0010: 01 53 47 24 40 00 80 06 31 28 C0 A8 00 05 C0 A8 .SG$@...1(......
0x0020: 00 03 01 BB 0A 20 25 99 2D 24 00 B6 41 BA 50 18 ..... %.-$..A.P.
0x0030: 42 66 B9 04 00 00 17 03 00 01 26 46 E4 32 33 3E Bf........&F.23>
0x0040: 1E 19 5E 9E FB DB 7F 55 41 73 09 9A 97 DE D7 65 ..^....UAs.....e
0x0050: A5 FD 00 0B 0B 9F 89 2A C2 4C 28 3B AD 0A 0A C9 .......*.L(;....
0x0060: A9 8D 57 54 AA DB 3D 53 9E C4 3D 0F 24 C8 DB 85 ..WT..=S..=.$...
0x0070: B8 2C 36 87 4E 1D 30 A5 2C F2 36 31 CC 48 58 69 .,6.N.0.,.61.HXi
0x0080: 3F A9 2A 8A 28 57 43 ED 4F C1 FF 2A B2 AF 2A BF ?.*.(WC.O..*..*.
0x0090: 23 54 F0 AB 9D 6F 5D 07 21 CF DF 07 2E 73 2D 5D #T...o].!....s-]
0x00A0: BC 18 8C E0 22 FA 84 80 17 EE 66 98 D9 CB 68 ED ....".....f...h.
0x00B0: 18 76 D2 DE E6 FA 6F B7 0B 09 AD 24 6B 8C 97 0E .v....o....$k...
0x00C0: 6F 26 8B 9F 58 ED FB 53 13 3E 1C 20 73 D3 BE A2 o&..X..S.>. s...
0x00D0: 8D C1 D2 20 09 F7 59 E1 9F D9 B2 84 49 58 DB 9F ... ..Y.....IX..
0x00E0: B7 61 AC E5 A2 56 C0 3F 6E 7E 67 54 4E B3 2E E1 .a...V.?n~gTN...
0x00F0: A8 F8 6C 87 95 7B 62 BD 6E 5B 70 28 3C 89 8E D4 ..l..{b.n[p(<...
0x0100: ED AB 3C E0 3E 75 5B DF BC 82 7C 4F C8 45 7C 66 ..<.>u[...|O.E|f
0x0110: FB 73 B8 29 CC 57 2D F2 5C 66 59 0E BE 4A 3B 42 .s.).W-.\fY..J;B
0x0120: 2F 5F 32 1E E2 DD FB C1 84 E9 07 0C DE CD 0B 72 /_2............r
0x0130: 91 F5 3C 61 6E FF 66 F1 D8 9B 7C CB 25 59 73 71 ..

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Wednesday 29 June 2011

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Sunday 26 June 2011

Customize Google to Improve Search Results



Customize GoogleGoogle is indisputedbly the best search engine out there on the Internet, however there are a few ways by which you can customize Google and make it even better. I have got 3 best free Firefox extensions using which you can customize Google by adding extra useful information to your search results andremove unwanted informationlike ads, spam and click tracking so as to improve the overall searching experience. The following are the 3 best extensions for Firefox using which you can improve the search results.
 

1. OptimizeGoogle:

 
Using OptimizeGoogle, you can get rid of text ads from Google search results, add links from about 10 other search engines, add position counter, product results and more. You can even filter your search results to see dead websites (using WayBack Machine) andremove click tracking so that you can search anonymously. Here is a list of some of the other useful features of this plugin.
1. Use Google suggest (get word suggestion while typing)
2. Add more security by using https wherever necessary
3. Filter spammy websites from search results page
4. Option to remove SideWiki
5. Add links to bookmark your favorite result
6. Add links to other news and product search sites
To install the plugin, just visit the OptimizeGoogle page from your Firefox browser and click on the Download button. Once installed, you can enable or disable the customization options from the Tools -> OptimizeGoogle Options.
After you customize Google to improve the search results, how about adding a feature that provides a way to preview the website in the search results itself? Here is a miracle Firefox extension to this job for us.
 

2.  SearchPreview:

 
SearchPreview (formerly GooglePreview) will insert thumbnail view of the webpage into the Google search results page itself so that you can take the guess work out of clicking a link. Just install the plugin, reload Firefox and you will have the SearchPreview at work. You can install this plugin from the following link.
OptimizeGoogle and SearchPreview have made our search results smarter and faster. Now how about safer? Well you have another Firefox plugin to make your search results safer as well. Here we go.
 

3. McAfee SiteAdvisor:

 
This is a free browser plugin that gives safety advice about websites on the search results page before you actually click on the links. After you install the SiteAdvisor plugin, you will see a small rating icon next to each search result which will alert you about suspecious/risky websites and help you find safer alternatives. These ratings are derived based on various tests conducted by McAfee.
Based on the quality of links, SiteAdvisor may display Green, Yellow, Red or Grey icon next to the search results. Green means that the link is completely safe, Yellow means that there is a minor risk, Red means a mojor risk and Grey means that the site is not yet rated. These results will guide you to Web safety.
SiteAdvisor works on both Internet Explorer and Firefox which you can download from the following link:
 
I hope you enjoy these 3 plugins which make your searching experience a lot more simpler and safer. Here is a snapshot of all the 3 plugins at work.
Custom Google Search Results
Popularity: 3% [?]

How to Detect Anonymous IP Addresses:For Those Who Make More Clever



Detect-ProxyAs the fraudsters are now becoming more sophisticated in bypassing the Geo-location controls by using proxies (Anonymous IPs) to spoof their IP address, it has become very much necessary to come up with a means for detecting the proxies so that the authenticity of the users can be verified. Using a proxy (web proxy) is the simplest and easiest way to conceal the IP address of an Internet user and maintain the online privacy. However proxies are more widely used by online fraudsters to engage in cyber crimes since it is the easiest way to hide their actual Geo-location such as city/country through a spoofed IP address. Following are some of the examples where fraudsters use the proxies to hide their actual IP.
 
1. Credit Card Frauds
For example, say a Nigerian fraudster tries to purchase goods online with a stolen credit card for which the billing address is associated with New York. Most credit card merchants use Geo-location to block orders from countries like Nigeria and other high risk countries. So in order to bypass this restriction the credit card fraudster uses a proxy to spoof his IP address so that it appears to have come from New York. The IP address location appears to be legitimate since it is in the same city as the billing address. A proxy check would be needed to flag this order.
 
2. Bypass Website Country Restrictions
Some website services are restricted to users form only a selected list of countries. For example, a paid survey may be restricted only to countries like United States and Canada. So a user from say China may use a proxy so as to make his IP appear to have come from U.S. so that he can earn from participating in the paid survey.
 

Proxy Detection Services

 
So in order to stop such online frauds, Proxy Detection has become a critical component. Today most companies, credit card merchants and websites that deal with e-commerce transactions make use of Proxy Detection Services like MaxMind andFraudLabs to detect the usage of proxy or spoofed IP from users participating online.
Proxy Detection web services allow instant detection of anonymous IP addresses. Even though the use of proxy address by users is not a direct indication of fraudulent behaviour, it can often indicate the intention of the user to hide his or her real IP. In fact, some of the most used ISPs like AOL and MSN are forms of proxies and are used by both good and bad consumers.
 
How Proxy Detection Works?
Proxy detection services often rely on IP addresses to determine whether or not the IP is a proxy. Merchants can obtain the IP address of the users from the HTTP header on the order that comes into their website. This IP address is sent to the proxy detecting service in real time to confirm it’s authenticity.
The proxy detection services on the other hand compare this IP against a known list of flagged IPs that belong to proxy services. If the IP is not on the list then it is authenticated and the confirmation is sent back to the merchant. Otherwise it is reported to be a suspected proxy. These proxy detection services work continuously to grab a list or range of IPs that are commonly used for proxy services. With this it is possible to tell whether or not a given IP address is a proxy or spoofed IP.
 
How to Tell Whether a given IP is Real or a Proxy?
There are a few free sites that help you determine whether or not a given IP is a proxy. You can use free services like WhatisMyIPAddress to detect proxy IPs. Just enter the suspected IP in the field and click on “Lookup IP Address” button to check the IP address. If it is a suspected proxy then you will see the results something as follows.
Detect Anonymous Proxy
So for all those who think that they can escape by using a spoofed IP, this post is the answer. I hope this information helps. Pass your comments.

How to Trace Mobile Numbers



Trace Mobile NumbersWith the rapid growth of mobile phone usage in recent years, we have often observed that the mobile phone has become a part of many illegal and criminal activities. So in most cases, tracing the mobile number becomes a vital part of the investigation process. Also sometimes we just want to trace a mobile number for reasons like annoying prank calls, blackmails, unknown number in a missed call list or similar.
Even though it is not possible to trace the number back to the caller, it is possible to trace it to the location of the caller and also find the network operator. Just have a look at this page on tracing Indian mobile numbers from Wikipedia. Using the information provided on this page, it is possible to certainly trace any mobile number from India and find out the location (state/city) and network operator (mobile operator) of the caller. All you need for this is only the first 4-digit of the mobile number. In this Wiki page you will find all the mobile number series listed in a nice tabular column where they are categorized based on mobile operator and the zone (state/city). This Wiki page is updated regularly so as to provide up-to-date information on newly added mobile number series and operators. I have used this page many a time and have never been disappointed.
If you would like to use a simpler interface where in you can just enter the target mobile number and trace the desired details, you can try this link from Numbering Plans. Using this link, you can trace any number in the world.
By using the information in this article, you can only know “where” the call is from and not “who” the caller is. Only the mobile operator is able to tell you ”who” the caller is. So if you’re in an emergency and need to find out the actual person behind the call, I would recommend that you file a complaint and take the help of police. I hope this information has helped you!

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How Antivirus Software Works



How antivirus works
Due to ever increasing threat from virus and other malicious programs, almost every computer today comes with a pre-installed antivirus software on it. In fact, an antivirus has become one of the most essential software package for every computer. Even though every one of us have an antivirus software installed on our computers, only a few really bother to understand how it actually works! Well if you are one among those few who would really bother to understand how an antivirus works, then this article is for you.
 

How Antivirus Works

 
An antivirus software typically uses a variety of strategies in detecting and removing viruses, worms and other malware programs. The following are the two most widely employed identification methods:
 

1. Signature-based dectection (Dictionary approach)

 
This is the most commonly employed method which involves searching for known patterns of virus within a given file. Every antivirus software will have a dictionary of sample malware codes called signatures in it’s database. Whenever a file is examined, the antivirus refers to the dictionary of sample codes present within it’s database and compares the same with the current file. If the piece of code within the file matches with the one in it’s dictionary then it is flagged and proper action is taken immediately so as to stop the virus from further replicating. The antivirus may choose to repair the file, quarantine or delete it permanently based on it’s potential risk. 
As new viruses and malwares are created and released every day, this method of detection cannot defend against new malwares unless their samples are collected and signatures are released by the antivirus software company. Some companies may also encourage the users to upload new viruses or variants, so that the virus can be analyzed and the signature can be added to the dictionary.
Signature based detection can be very effective, but requires frequent updates of the virus signature dictionary. Hence the users must update their antivirus software on a regular basis so as to defend against new threats that are released daily.
 

2. Heuristic-based detection (Suspicious behaviour approach)

 
Heuristic-based detection involves identifying suspicious behaviour from any given program which might indicate a potential risk. This approach is used by some of the sophisticated antivirus softwares to identify new malware and variants of known malware. Unlike the signature based approach, here the antivirus doesn’t attempt to identify known viruses, but instead monitors the behavior of all programs.
For example, malicious behaviours like a program trying to write data to an executable program is flagged and the user is alerted about this action. This method of detection gives an additional level of security from unidentified threats.
File emulation: This is another type of heuristic-based approach where a given program is executed in a virtual environment and the actions performed by it are logged. Based on the actions logged, the antivirus software can determine if the program is malicious or not and carry out necessary actions in order to clean the infection.
Most commercial antivirus softwares use a combination of both signature-based and heuristic-based approaches to combat malware.
 

Issues of concern

 
Zero-day threats: A zero-day (zero-hour ) threat or attack is where a malware tries to exploit computer application vulnerabilities that are yet unidentified by the antivirus software companies. These attacks are used to cause damage to the computer even before they are identified. Since patches are not yet released for these kind of new threats, they can easily manage to bypass the antivirus software and carry out malicious actions. However most of the threats are identified after a day or two of it’s release, but damage caused by them before identification is quite inevitable.
Daily Updates: Since new viruses and threats are released everyday, it is most essential to update the antivirus software so as to keep the virus definitions up-to-date. Most softwares will have an auto-update feature so that the virus definitions are updated whenever the computer is connected to the Internet.
Effectiveness: Even though an antivirus software can catch almost every malware, it is still not 100% foolproof against all kinds of threats. As explained earlier, a zero-day threat can easily bypass the protective shield of the antivirus software. Also virus authors have tried to stay a step ahead by writing “oligomorphic“, “polymorphic” and, more recently, “metamorphic” virus codes, which will encrypt parts of themselves or otherwise modify themselves as a method of disguise, so as to not match virus signatures in the dictionary.
Thus user education is as important as antivirus software; users must be trained to practice safe surfing habits such as downloading files only from trusted websites and not blindly executing a program that is unknown or obtained from an untrusted source. I hope this article will help you understand the working of an antivirus software
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