SEMINAR REPORT
ON
WEB SPOOFING
Submitted in
Partial Fulfillment of the Requirements for the
Degree of
Bachelor Engineering
IN
COMPUTER SCIENCE & ENGINEERING
Session: 2008-09
Submitted To: Submitted By:
Miss. Shubhra Saxena Varun Kumar
(Lecturer ,Computer Science) VIIIth Sem
(C.S.E)
DEPARTMENT OF COMPUTER SCIENCE & ENGINEERING
Yagyavalkya Institute of Technology,
Sitapura, Jaipur
25th March, 2009
ACKNOWLEDGEMENTS
I express my sincere thanks to Mr.Kailash Maheshwari (Head of the
Department, Computer Science and Engineering, YIT), Mr. Lokesh Sharma and Miss.
Shubhra Saxena for their kind co-operation for presenting the seminar.
I also extend my sincere thanks to all other faculty members of Computer Science
and Engineering Department and for their co-operation and encouragement.
Varun Kumar
CERTIFICATE
This is certifiy that Mr. Varun Kumar from COMPUTER SCIENCE AND ENGINEERING has successfully
delivered a seminar on the topic ” Web Spoofing ” and has submitted a satisfactory report about it as
per partial fulfillment of the requirement for the degree of B.E. (Comp.Sc.) according to the syallbus of
UNIVERSITY OF RAJASTHAN , JAIPUR during the academic year 2008-09.
Date:25th March 09
Mr.Kailash Maheshwari Miss. Shubhra Saxena
( H.O.D ,C.S.E & I.T ) ( Seminar Guide )
Preface
The Web is currently the pre-eminent medium for electronic service delivery to remote users. As a consequence,authentication of servers is more important than ever. Even sophisticated users base their decision whether or not to trust a site on browser cues—such as location bar information, SSL icons, SSL warnings, certificate information,response time, etc.
In the seminal work on web spoofing, Felten et al showed how a malicious server could forge some of these cues—but using approaches that are no longer reproducible. However, subsequent evolution of Web tools has not only patched security holes—it has also added new technology to make pages more interactive and vivid. In this paper, we explore the feasibility of web spoofing using this new technology—and we show how, in many cases, every one of the above cues can be forged.
CONTENTS
1. Acknowledgement 22. Preface 33. Certificate 44. Contents 55. Introduction 66. Spoofing attack 107. How the attack works 138. Background 17
1.Anatomy of Browser Window2.Web Spoofing
9. Previous work 211.Princeton2.UCSB 3.CMU
10. Consequences 221.Surveillance 2.Tampering3.Spoofing the Whole Web
11. Remedies 23Short-term & Long-term Solution
12. Limitations 24 13. Conclusion 25 14. Reference and Bibliography 26
Introduction
Nearly every aspect of social, government, and commercial activity is moving into electronic settings. TheWorldWideWeb is the de facto standard medium for these services. Inherent properties of the physical world make it sufficiently difficult to forge a convincing storefront or ATM that successful attacks create long-cited anecdotes . As a consequence, users of physical services—stores, banks, newspapers—have developed a reasonably effective intuition of when to trust that a particular service offering is exactly what it appears to be. However, moving from “bricks and mortar” to electronic introduces a fundamental new problem: bits are malleable. Does this intuition still suffice forthe new electronic world? When one clicks on a link that says “Click Here to go to TrustedStore.Com,” how does one know that’s where one has been taken?
Answering these questions require examining how users make judgments about whether to trust a particularWeb pagefor a particular service. Indeed, the issue of user trust judgment is largely overlooked; research addressing how to secure Web servers, how to secure the client-server connection, and how to secure client-side management risk being rendered moot, if the final transmission of trust information the human user is neglected.
Users now routinely encounter Web (and Web-like) content as the alleged manifestation of some specific entity—a newspaper, a store, a government agency. How do users evaluate whether or not this manifestation is genuine? We briefly discuss some items that have re-surfaced recently.
_ Convincing HTML. Once upon a time, e-mail consisted solely of text. However, mail tools have become sufficiently powerful that HTML attached to an email will be automatically rendered at the receiver’s site. Amalicious party can forge a news article by downloading legitimate HTML from a Web server, editing it, andattaching it to email.One might expect that recipients should know that Web pages should be viewed via Web transfers, not via email. However, law enforcement colleagues of ours report that this technique is sufficiently convincing to be a continuing source of problems.
_ Convincing URL. More sophisticated users may base their decisions on the URL their browser tells them they are visiting. However, RFC 1738 permits more flexibility than many people realize. For a basic example, the hostname can be an IP address.As a case in point, in 1999, Gary D. Hoke created HTML that produced a realistic-looking Bloomberg press release pertaining to PairGain Technologies, Inc., posted this on angelfire.com, and posted a link to this page on a stock discussion bboard. Since the presence of angelfire.com instead of bloomberg.com in the URL might give away the hoax, Hoke disguised the link using by using Angelfire’s IP address instead: http://204.238.155.37/biz2/headlines/topfin.htmlHoke’s limited disguise was sufficient to drive the price of the stock up by a third (and also land him in legaltrouble). However, the technology permits even more convincing disguises. For one thing, on many platforms(including all the Netscape installations we tested, except Macs), the IP address can be expressed as a decimal number (e.g., 3438189349) instead of the more familar slot-dot notation—further disguising things.Furthermore, (as pointed out yet again in) RFC 1738 permits the hostname portion to include a username and password in addition to machine name. Hoke could have made his hoax even more convincing by finding (or setting up) a server that accepts arbitrary user names and passwords, and giving a URL of the formhttp://bloomberg.com:biz@3438189349/headlines/topfin.html
_ Typejacking. URLs that appear more standard—but contain incorrect hostnames deceptively similar to hostnames users expect—is a trick long-used by many e-commerce vendors (primarily pornographers) to lure in unwitting customers.However, this technique can also be used maliciously. As we recently saw in the headlines, attackers established a clone of the paypal Web site at a hostname paypai, and used email to lure unsuspecting users to log in—and reveal their PayPal passwords. The fact that many mailers let a
user simply click on a link, instead of pasting or typing it into a browser, and that in many fonts, a lower-case “i” is indistinguishable froma lower-case “l”, facilitated this attack.
_ SSL to whom? Secure Sockets Layer (SSL) is touted as the solution to secure Web connections and server impostors. However, even if a user can figure out how to examine the certificate testifying to a server’s identity, it is not clear whether this information provides sufficient grounds for trust. For example, the Palm Computing“secure” web site is protected by an SSL certificate registered to Modus Media. Is Modus Media authorized to act for Palm Computing? (It turns out, yes. But how is the user to know?)It is against this background that we started our work. The current visual signals that a browser provides do not appearto provide enough information for many trust judgments the user needs to make. But before we examine how to extend the browser user interface to handle things like security attribute certificates or delegation for servers, we need to examine whether the insufficient information the browsers do provide is reliable. The seminal web spoofing work of Felten et al showed that, in 1996, a malicious site could forge many of these clues. Subsequent researchers reported difficulty reproducing these results. This scenario raises the question: What’s still spoofable today, in 2001?Our answer: for standard browser installations, just about everything: including the existence of SSL sessions and thealleged certificates supporting them.To return to our earlier question: how does one know the click has really taken one to TrustedStore.com? One cannot.On common Netscape and Internet Explorer platforms, if one surfs with JavaScript enabled, an adversary site canconvincingly spoof the clues and appropriate behavior.Section 2 establishes the background: the elements of Web pages, Web surfing, and advanced content tools. Section 3discusses previous efforts in this area. Section 4 presents the sequence of techniques that we developed. Section 5sketches some interesting extensions of these techniques. Section 6 concludes with some avenues for future work.
Spoofing AttacksIn a spoofing attack, the attacker creates misleading context in order to trick the victim
into making an inappropriate security-relevant decision. A spoofing attack is like a con game: the attacker sets up a false but convincing world around the victim. The victim does something that would be appropriate if the false world were real. Unfortunately, activities that seem reasonable in the false world may have disastrous effects in the real world.
Spoofing attacks are possible in the physical world as well as the electronic one. For example, there have been several incidents in which criminals set up bogus automated-teller machines1, typically in the public areas of shopping malls. The machines would accept ATM cards and ask the person to enter their PIN code. Once the machine had the victim’s PIN, it could either eat the card or “malfunction” and return the card. In either case, the criminals had enough information to copy the victim’s card and use the duplicate. In these attacks, people were fooled by the context they saw: the location of the machines, their size and weight, the way they were decorated, and the appearance of their electronic displays. People using computer systems often make security-relevant decisions based on contextual cues they see. For example, you might decide to type in your bank account number because you believe you are visiting your bank’s Web page. This belief might arise because the page has a familiar look, because the bank’s URL appears in the browser’s location line, or for some other reason. To appreciate the range and severity of possible spoofing attacks, we must look more deeply into two parts of the definition of spoofing: security-relevant decisions and context.
Security-relevant DecisionsBy “security-relevant decision,” we mean any decision a person makes that might lead to
undesirable results such as a breach of privacy or unauthorized tampering with data. Deciding to divulge sensitive information, for example by typing in a password or account number, is one example of a security-relevant decision. Choosing to accept a downloaded document is a security-relevant decision, since in many cases a downloaded document is capable of containing malicious elements that harm the person receiving the document2. Even the decision to accept the accuracy of information displayed by your computer can be security-relevant. For example, if you decide to buy a stock based on information you get from an online stock ticker, you are trusting that the information provided by the ticker is correct. If somebody could present you with incorrect stock prices, they might cause you toengage in a transaction that you would not have otherwise made, and this could cost you money.
ContextA browser presents many types of context that users might rely on to make decisions. The
text and pictures on a Web page might give some impression about where the page came from; for example, the presence of a corporate logo implies that the page originated at a certain corporation.The appearance of an object might convey a certain impression; for example, neon green text on a purple background probably came from Wired magazine. You might think you’re dealing with a popup window when what you are seeing is really just a rectangle with a border and a color different from the surrounding parts of the screen. Particular graphical items like file-open dialog boxes are immediately recognized as having a certain purpose. Experienced Web users react to such cues in the same way that experienced drivers react to stop signs without reading them. The names of objects can convey context. People often deduce what is in a file by its name.
Is manual.doc the text of a user manual? (It might be another kind of document, or it might not be a document at all.) URLs are another example. Is MICR0S0FT.COM the address of a large software company? (For a while that address pointed to someone else entirely. By the way, the round symbols in MICR0S0FT here are the number zero, not the letter O.) Was dole96.org Bob Dole’s 1996 presidential campaign? (It was not; it pointed to a parody site.)
People often get context from the timing of events. If two things happen at the same time, you naturally think they are related. If you click over to your bank’s page and a username/password dialog box appears, you naturally assume that you should type the name and password that you use for the bank. If you click on a link and a document immediately starts downloading, you assume that the document came from the site whose link you clicked on. Either assumption could be wrong.If you only see one browser window when an event occurs, you might not realize that the event was caused by another window hiding behind the visible one.Modern user-interface designers spend their time trying to devise contextual cues that will guide people to behave appropriately, even if they do not explicitly notice the cues. While this is usually beneficial, it can become dangerous when people are accustomed to relying on context that is not always correct.
TCP and DNS SpoofingAnother class of spoofing attack, which we will not discuss here, tricks the user’s
software into an inappropriate action by presenting misleading information to that software3. Examples of such attacks include TCP spoofing4, in which Internet packets are sent with forged return addresses, and DNS spoofing5, in which the attacker forges information about which machine names correspond to which network addresses. These other spoofing attacks are well known, so we will not discuss them further.
Web SpoofingWeb spoofing is a kind of electronic con game in which the attacker creates a convincing
but false copy of the entire World Wide Web. The false Web looks just like the real one: it has all the same pages and links. However, the attacker controls the false Web, so that all network traffic between the victim’s browser and the Web goes through the attacker.
How the Attack WorksThe key to this attack is for the attacker’s Web server to sit between the victim and the
rest of the Web. This kind of arrangement is called a “man in the middle attack” in the security literature.
URL RewritingThe attacker’s first trick is to rewrite all of the URLs on some Web page so that they
point to the attacker’s server rather than to some real server. Assuming the attacker’s server is on the machine www.attacker.org, the attacker rewrites a URL by adding http://www.attacker.org to the front of the URL. For example,http://home.netscape.com becomes http://www.attacker.org/http://home.netscape.com. (The URL rewriting technique has been used for other reasons by several other Web sites, including theAnonymizer and the Zippy filter. See page 9 for details.) Figure 1 shows what happens when the victim requests a page through one of the rewritten URLs. The victim’s browser requests the page from www.attacker.org, since the URL starts with http://www.attacker.org. The remainder of the URL tells the attacker’s server where on the Web to go to get the real document.
Figure 1: An example Web transaction during a Web spoofing attack. The victim requestsa Web page. The following steps occur: (1) the victim’s browser requests the page fromthe attacker’s server; (2) the attacker’s server requests the page from the real server; (3) thereal server provides the page to the attacker’s server; (4) the attacker’s server rewrites thepage; (5) the attacker’s server provides the rewritten version to the victim.
Once the attacker’s server has fetched the real document needed to satisfy the request, the attacker rewrites all of the URLs in the document into the same special form by splicing http://www.attacker.org/ onto the front. Then the attacker’s server provides the rewritten page to the victim’s browser.Since all of the URLs in the rewritten page now point to www.attacker.org, if thevictim follows a link on the new page, the page will again be fetched through the attacker’s server. The victim remains trapped in the attacker’s false Web, and can follow links forever without leaving it.
FormsIf the victim fills out a form on a page in a false Web, the result appears to be handled properly. Spoofing of forms works naturally because forms are integrated closely into the basic Web protocols: form submissions are encoded in Web requests and the replies are ordinary HTML. Since any URL can be spoofed, forms can also be spoofed.When the victim submits a form, the submitted data goes to the attacker’s server. The attacker’s server can observe and even modify the submitted data, doing whatever malicious editing desired, before passing it on to the real server. The attacker’s server can also modify the data returned in response to the form submission.
“Secure” connections don’t helpOne distressing property of this attack is that it works even when the victim requests a
page via a “secure” connection. If the victim does a “secure” Web access ( a Web access using the Secure Sockets Layer) in a false Web, everything will appear normal: the page will be delivered, and the secure connection indicator (usually an image of a lock or key) will be turned on. The victim’s browser says it has a secure connection because it does have one. Unfortunately the secure connection is to www.attacker.org and not to the place the victim thinks it is.The victim’s browser thinks everything is fine: it was told to access a URL atwww.attacker.org so it made a secure connection to www.attacker.org. Thesecure-connection indicator only gives the victim a false sense of security.
Starting the AttackTo start an attack, the attacker must somehow lure the victim into the attacker’s false
Web. There are several ways to do this. An attacker could put a link to a false Web onto a popular Web page. If the victim is using Web-enabled email, the attacker could email the victim a pointer to a false Web, or even the contents of a page in a false Web. Finally, the attacker could trick a Web search engine into indexing part of a false Web.
Completing the IllusionThe attack as described thus far is fairly effective, but it is not perfect. There is still some
remaining context that can give the victim clues that the attack is going on. However, it is possible for the attacker to eliminate virtually all of the remaining clues of the attack’s existence. Such evidence is not too hard to eliminate because browsers are very customizable. The ability of a Web page to control browser behavior is often desirable, but when the page is hostile it can be dangerous.
The Status LineThe status line is a single line of text at the bottom of the browser window that displays
various messages, typically about the status of pending Web transfers.The attack as described so far leaves two kinds of evidence on the status line. First, when the mouse is held over a Web link, the status line displays the URL the link points to. Thus, the victim might notice that a URL has been rewritten. Second, when a page is being fetched, the status line briefly displays the name of the server being contacted. Thus, the victim might notice that www.attacker.org is displayed when some other name was expected. The attacker can cover up both of these cues by adding a JavaScript program to every rewritten page. Since JavaScript programs can write to the status line, and since it is possible to bind JavaScript actions to the relevant events, the attacker can arrange things so that the status line participates in the con game, always showing the victim what would have been on the status line in the real Web. This makes the spoofed context even more convincing.
The Location LineThe browser’s location line displays the URL of the page currently being shown. The
victim can also type a URL into the location line, sending the browser to that URL. The attack as described so far causes a rewritten URL to appear in the location line, giving the victim a possible indication that an attack is in progress.This clue can be hidden using JavaScript. A JavaScript program can hide the real location line and replace it by a fake location line that looks right and is in the expected place. The fake location line can show the URL the victim expects to see. The fake location line can also accept keyboard input, allowing the victim to type in URLs normally. The JavaScript program can rewrite typed-in URLs before they are accessed.
Viewing the Document SourcePopular browsers offer a menu item that allows the user to examine the HTML source for
the currently displayed page. A user could possibly look for rewritten URLs in the HTML source, and could therefore spot the attack.The attack can prevent this by using JavaScript to hide the browser’s menu bar, replacing it with a menu bar that looks just like the original. If the user chose “view document source” from the spoofed menu bar, the attacker would open a new window to display the original (non-rewritten) HTML source.
Viewing Document InformationA related clue is available if the victim chooses the browser’s “view document
information” menu item. This will display information including the document’s URL. As above, this clue can be spoofed by replacing the browser’s menu bar. This leaves no remaining visible clues to give away the attack.
BackgroundNearly all Internet users are familiar with the look and feel of Web pages and Web
surfing. In this section, we quickly introduce the elements and the underlying technology, to establish a common terminology for the rest of the paper.
1 Anatomy of Browser WindowWe start by quickly reviewing the elements of a browser window, using Netscape’s
“Classic” format. (See Figure 1.) The top line—with “File, Edit...” tags—is the menu bar. The next line—with “Back, Forward...” buttons— is the tool bar. Below the tool bar is the location bar, containing additional buttons as well as the location line, which displays the currently visited URL. Below the location bar is the personal bar. The main window is next; at the bottom, the status bar contains the SSL icon—which indicates whether or not an SSL session is established—as well as the status line, which indicates various status information, such as the URL associated with the hyperlink underneath the cursor. An input field is the portion of a Web page that collects input from users.
Interaction In a normal browser window, many of these elements are not static. Rather, user
operations—such as moving a mouse over or clicking on an element—cause some corresponding reaction, such as displaying a pop-up menu. Typing into the location line and hitting return causes the browser to load that page.
SurfingIn the typical act of browsing, the user selects (via clicking a link, or typing a URL) a
Web site; that server returns an HTML file which the browser renders. Potentially, the file causes the browser to fetch and load other files from that server and other servers.In a typical SSL session, the browser and server encrypt transmissions using shared session keys. The existence of an SSL session is indicated by the SSL icon; depending on configuration and platform, entering and exiting an SSL session (as well, potentially, other relevant SSL events) triggers the display of a warning window, usually with an“OK” or “OK, Cancel, Help” buttons.
2 Web SpoofingFor this paper, we offer this working definition of web spoofing: when malicious action
causes the reality of the browsing session to differ significantly from the mental model a sophisticated user has of that session. In our work, we confine this malicious action to content from a conspiracy of servers: e.g., the server that offers the fake “click here for TrustedStore.Com” link, and the server that offers the faked pages. In particular, we do not permit
Figure 1 Elements of a typical browser window.
the adversarial servers to have signed scripts, and we will regard the the user’s browser and computing platform to be out of the reach of an adversary. (Although, when one thinks of the many non-Netscape and non-Adobe sites that say “click here for the latest version of Netscape” or “click here to get Acrobat,” Web spoofing could enable some very interesting platform attacks.) In a typical Web spoofing attack, the attacker presents the client carefully designed web pages, and tricks the client to believe that he is communicating with a real server instead. Web spoofing is possible because the information which the server provides to the user is collected and displayed by the browser. Even in SSL sessions, the user judges whether a connection is secure based on information like the SSL icon, warning windows, location information, and certificates. But the user does not receive this information directly; rather, he draws conclusions from what the browser appears to tell him.
Advanced Content Tools The key to Web spoofing is the fact that simple “hypertext markup” (the “HT” of
“HTML”) has never been good enough. Web developers have continually wanted more interaction and flash than simple hypertext markup provides, and have developed a sequence of ways to embed executable content inWeb pages.Currently, the primary parameters here are:_ the language of the executable,_ and the location where it runs.
For languages, Java and JavaScript are two that are commmonly used. For location, the primary choice is at the client, or at the server. Examples of server-side executables—acting under the requests coming from the client side (but not necessarily from the user) are servlets and CGI scripts. For client-side execution, Dynamic HTML (DHTML) has come to be the widely-accepted catch-all term for using HTML, Cascading Style Sheets (CSS), JavaScript, and other techniques to create vivid, interactive pages that depend primarily on client-side execution.It is true that the emergence of executable Web content coincided with an increased focus on security—since, without further countermeasures, the act of browsing could cause an unwitting client to download and execute malicious code. However, this security work has been concerned with how to prevent malicious code from stealing sensitive information from the local disk or other web pages the client browses, and from tampering with the data that client has or shares with other servers. (For example, both Java applet and JavaScript by default have almost no access to local files.) Ironically, this security focus is completely inappropriate for Web spoofing: where the goal of the content is not to illegally modify client-side data, but rather to mislead the client, so that he/she gives the sensitive data out by mistake. Too often, traditional security models do not include user trust judgment!
Previous Works
1.Princeton As early as 1996, Felten et al at Princeton originated the term web spoofing and explored spoofing attacks on Netscape Navigator and Microsoft Internet Explorer that allowed an attacker to create a “shadow copy” of the true web. When the victim accesses the shadow Web through the attacker’s servers, the attacker can monitor all of the victim’s activities and get or modify the information the victim enters, including passwords or credit card numbers.
Source code is not available; according to the paper, the attack used JavaScript to rewrite the hyperlink information shown on the status bar; to hide the real location bar and replace it with a fake one that also accept keyboard input, allowing the victim to type in URLs normally (which then get rewritten to go the attacker’s machine); and to replace the Document Source button the menu bar (to show the source the victim expects, not the real source). Apparently unable to spoof the SSL icon, the Princeton attack spoofed SSL by having the user open a real SSL session to the attacker’s machine.
2.UCSB Subsequently, De Paoli et al at UCSB [4] tried to repeat the Princeton attack, but could
no longer fake the location bar of Netscape Navigator using JavaScript. However, De Paoli did show how the features in Java and JavaScript can be used to launch two kinds of attacks in standard browsers. One attack is using a Java applet to collect and send information back to its server. A client downloads a honey-pot HTML document that embeds a spy applet with its stop method overridden (although this enabling technique has since been deprecated). From then on, every time the client launches a new web page with an embedded Java applet, a new Java thread starts. But since the stop method of the spy applet is overridden, the spy thread continues running—and collects information on the new client-side Java threads, and sends them back to the attacker. The other attack uses a Java applet to detect when the victim visits a certain website, then displays an impostor page for that site in order to steal sensitive information, such as credit card number.
3.CMU In 1996, Tygar and Whitten from CMU [20] demonstrated how a Java applet or similar
remote execution can be used as a trojan horse. The Java applet could be inserted into a client machine through a bogus remote page and pop up a dialog window similar to the true login windows. With the active textfield on the top of the image, the trojan horse applet would capture the keyboard input and transfer them to attacker’s machine. Tygar and Whitten also gave a way to prevent these attack: window personalization. None of these papers investigated how to forge SSL connections, when no SSL connection exists.
CONSEQUENSESSince the attacker can observe or modify any data going from the victim to Web servers,
as well as controlling all return traffic from Web servers to the victim, the attacker has many possibilities. These include surveillance and tampering.
-Surveillance The attacker can passively watch the traffic, recording which pages the victim visits and
the contents of those pages. When the victim fills out a form, the entered data is transmitted to a Web server, so the attacker can record that too, along with the response sent back by the server. Since most on-line commerce is done via forms, this means the attacker can observe any account numbers or passwords the victim enters. As we will see below, the attacker can carry out surveillance even if the victim has a “secure” connection (usually via Secure Sockets Layer) to the server, that is, even if the victim’s browser shows the secure-connection icon (usually an image of a lock or a key).
-Tampering The attacker is also free to modify any of the data traveling in either direction between
the victim and the Web. The attacker can modify form data submitted by the victim. For example, if the victim is ordering a product on-line, the attacker can change the product number, the quantity, or the ship-to address.The attacker can also modify the data returned by a Web server, for example by inserting misleading or offensive material in order to trick the victim or to cause antagonism between the victim and the server.
Spoofing the Whole WebYou may think it is difficult for the attacker to spoof the entire World Wide Web, but it is
not. The attacker need not store the entire contents of the Web. The whole Web is available on-line; the attacker’s server can just fetch a page from the real Web when it needs to provide a copy of the page on the false Web.
RemediesWeb spoofing is a dangerous and nearly undetectable security attack that can be carried
out on today’s Internet. Fortunately there are some protective measures you can take.
Short-term SolutionIn the short run, the best defense is to follow a three-part strategy:
1. disable JavaScript in your browser so the attacker will be unable to hide the evidence of the attack;2. make sure your browser’s location line is always visible;3. pay attention to the URLs displayed on your browser’s location line, making sure they always point to the server you think you’re connected to.
This strategy will significantly lower the risk of attack, though you could still be victimized if you are not conscientious about watching the location line.At present, JavaScript, ActiveX, and Java all tend to facilitate spoofing and other security attacks, so we recommend that you disable them. Doing so will cause you to lose some useful functionality, but you can recoup much of this loss by selectively turning on these features when you visit a trusted site that requires them.
Long-term SolutionWe do not know of a fully satisfactory long-term solution to this problem.
Changing browsers so they always display the location line would help, although users would still have to be vigilant and know how to recognize rewritten URLs. This is an example of a “trusted path” technique, in the sense that the browser is able to display information for the user without possible interference by untrusted parties. For pages that are not fetched via a secure connection, there is not much more that can be done. For pages fetched via a secure connection, an improved secure-connection indicator could help. Rather than simply indicating a secure connection, browsers should clearly say who is at the other end of the connection. This information should be displayed in plain language, in a manner intelligible to novice users; it should say something like “Microsoft Inc.” Rather than “www.microsoft.com.” Every approach to this problem seems to rely on the vigilance of Web users. Whether we can realistically expect everyone to be vigilant all of the time is debatable
Limitations
1. The scenario : i was unable to present the complete scenario of web spoofing as per the practical field is concerned. This may also include the lack of knowledge in programming language like java for the better understanding of code level spoofing and again to work against Advance tools like antiviruses and antispywares.
2. Fake Interaction : unable to examine the fake encounter.
3. Availability of books also bounded my approach.
Conclusions
In 2001, the original Princeton attacks may not be directly reproducible; but inspired by them, we have shown even more extensive spoofing is now possible. Research in computer science, perhaps more than other fields, requires saying things in the language of each component of one’s audience. One component is only convinced by seeing real code work. As Tygar and Whitten point out, customization is an effective way to prevent web spoofing. Although unsigned JavaScript can detect the platform and browser the client is using, it cannot (yet) detect the detailed window setting which may affect the browser display.
Since the initial motivation was not to attack but to defend: to “build a better browser” that, for example, could clearly indicate security attributes of a server (and so enable clients to securely use our server-hardening techniques. We hope to use our understanding of spoofing is to build something that might be unspoofable.
References
[1] E. W. Felten, D. Balfanz, D. Dean and D. Wallach. Web Spoofing: An Internet Con Game. Technical Report 54-96 (revised). Deptarmtent of Computer Science, Princeton University. February 1997.
[2] R. J. Barbalace. “Making something look hacked when it isn’t.” The Risks Digest, 21.16, December 2000.
[3] Dynamic HTML Lab. http://www.webreference.com/dhtml/.
[4] Carl Ellison. Personal communication, September 2000.
