Institute of Technology,

Nirma University.

M.Tech CASAD Semester I

Cyber Security 2014-2015

Sem II

Assignment III

Tejas M. PatilRoll no. 14MCLC22M. Tech. 1st Year

Due date - 14th March 2015

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Question 1.1Why websites tracks the user activities? Give 3 examples.

Answer,- Websites track user activities to understand the pattern in theirweb browsing, subsequently profiling their needs, interests and frequent visits.Websites can make money off of this information by selling it to interestedbuyers or using to increase the number of hits on their websites.

Examples

• Google sponsored ads They are based on our google searches. Also theyare available on lots of google sponsored website.

• Youtube Video suggestions on youtube are chiefly based on our previousyoutube history.

• Others trackers such as Facebook connect, Google analytics, Taboolawhich can be seen through Ghostery Add on in Firefox.

Question 1.2Why websites uses the cookies? What are that? How they are used ? Howtwitter and facebook are using cookies?Answer,-

Cookies are used by website to temporarily store the personal settings on ourhard drive. Cookies are popular because they solve a big problem for Web sites.Cookie allows a site to store state of our browsing information on our machine.There are many reasons a given site would wish to use cookies. These rangefrom the ability to personalize information (like on My Yahoo or Excite), or tohelp with on-line sales/services (like on Amazon Books or eBay), or simply forthe purposes of collecting demographic information (like DoubleClick). Cookiesalso provide programmers with a quick and convenient means of keeping sitecontent fresh and relevant to the user’s interests.According to twitter official website : They use cookies for-

1. Authentication and security

2. Preferences

3. Analytics and research

4. Personalized content

5. Advertising

According to Facebook official website : They use cookies for-

1. Authentication

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2. Security and site integrity

3. Advertising, insights and measurement

4. Localization

5. Site features and services

6. Performance

7. Analytics and research

Question 1.3How cookies represent treat in cyber world?Answer,-

Cookie by itself is just a piece of information and not a program code. Itis not capable of harming user’s computer, and they cannot act as a virus orworms. Cookies are created and used to allow server to store and retrieve stateinformation. However, this small text file is rich in information, which may in-clude users IP address, user name, email address, password, preferred language,shopping cart items and any strings that can be linked to users identity.

There’s a privacy issue if the cookie is stored in users’ computer withouthis/her knowledge or consent and this also includes affiliates or third-partycookies.The cookie header and content are readable or in clear text format. Any sensitiveor identifiable information is vulnerable and exposed to threats whether it is amalware, packet sniffers, cookie hijackers or another user of that pc.

Persistent cookies does not expire soon enough even after the user endedthe session. Thus, the website can build information or profile your browsingactivity and preferences over time.

Cookie poisoning simply means performing unauthorized modification of thevalues stored inside the cookie. This can be easily done using tools and infor-mation available from the internet. Most websites stores persistent, non-securecookies while some are secured but still there are web site that employs poorencryption that could be easily decoded.Worms - Mass-mailing worms such as NetSky and Lohack is capable to searchand harvest email address to all .TXT files and this includes users’ cookies.Trojan - Banking related trojans are usually capable of stealing users’ cookies.Backdoor - There are backdoor that steals cookies associated to ebay, paypaland banks.Exploit - This is usually employed using cross site scripting exploit, where amalicious user injects a code to a legitimate vulnerable website. So, all visitorsof that website will get redirected where a malicious cookie stealer script awaits.

Question 1.44. Give examples of web bug and web sniffers in cyber world. [List and give

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their functionality]Answer,-A web bug is an object embedded in a web page or email, which unobtrusively(usually invisibly) allows checking that a user has accessed the content. Com-mon uses are email tracking and page tagging for web analytics. Alternativenames are web beacon, tracking bug, tag, or page tag. Common names for webbugs implemented through an embedded image include tracking pixel, pixel tag,11 gif, and clear gif. When implemented using JavaScript, they may be calledJavaScript tags.A web sniffers monitor data flowing over computer network links. It can bea self-contained software program or a hardware device with the appropriatesoftware or firmware programming. Sniffers examine network traffic, making acopy of the data but without redirecting or altering it. Some sniffers work onlywith TCP/IP packets, but the more sophisticated tools can work with manyother protocols and at lower levels including Ethernet frames.

Question 1.5What is the difference between Cookies, Web bugs and Web Trackers? How doyou know their presence?Answer,-

Cookies are used by website to temporarily store the personal settings onour hard drive. They can be found in users hard disk (C drive).A web bug is an object embedded in a web page or email, which unobtrusively(usually invisibly) allows checking that a user has accessed the content. Theycan be detected by using privacy softwares like McAfee privacy services, Bug-nosis, AdMuncher etc.Website trackers perform activity (and ability) of a website (using special soft-ware tools) to keep tabs on website visitors. They can be detected by usingGhostery or Lightbeam add ons in Firefox.

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