Analytics // Security Monitoring
7/27/2012
11:26 PM
Connect Directly
RSS
E-Mail
50%
50%

Web Browser Weaknesses Make Tracking Easy

Researcher kicks off effort to catalog all the ways that browsers and popular add-ons can be used to track users

While users generally do not like the idea of being tracked as they browse online, there are any number of legitimate reasons for tracking visitors to your Web site: counting unique users, tracking browsing behavior, and even security.

   
Click here for more of Dark Reading's Black Hat articles.

Companies that are interested in monitoring the comings and goings of potentially bad actors can also benefit from better tracking techniques. At the Black Hat conference in Las Vegas, senior security consultant Gregory Fleischer of FishNet Security cataloged the ways that companies can fingerprint visitors' browsers and systems, track their visits, and further unmask their identities.

Echoing Sun Microsystems CEO Scott McNealy's infamous comment from 1999 -- "You have zero privacy anyway, get over it." -- Fleischer told attendees not to expect websites to give up tracking users.

"Web tracking is inevitable -- it is going to happen, and it's here to stay," he said. "It will be more pervasive in the future."

Many of the design decisions used to increase browser functionality also allow sites to more persistently track their visitors. Tracking makes uses of information leaked by a browser, either because of a design weakness or just as an offshoot of the browser's normal functionality.

"Ultimately, an effective tracking solution needs to encompass all facets of information exposed by the browser, but care should be taken to avoid relying on user cooperation, deception, or outright theft of user information," Fleischer stated in his whitepaper on the topic.

[ A security research group uses cached JavaScript to control computers connecting to a malicious proxy, gaining intelligence on fraudsters and criminals. See JavaScript Botnet Sheds Light On Criminal Activity. ]

Fingerprinting allows the tracker to keep tabs on a user, even when he may take actions to foil the eavesdropping. In particular, the plug-ins installed by a user can help websites create a better fingerprint of the user's system. For example, the existence of NoScript, a popular Firefox plug-in that blocks unwanted Javascript from running, can be detected and become a component in a robust fingerprint, Fleischer said.

Because plug-ins offer more detailed access to machine-specific and software-specific characteristics, they can create better fingerprints of systems and help track visitors more reliably. Ubiquitous plug-ins -- such as Adobe Flash and Acrobat, Microsoft Silverlight, and Oracle's Java -- can all reveal system data that can identify a system. Java, in particular, can be used to collect information that can make up a more reliable fingerprint.

"When you have Java installed, it is very easy to set an ID," he said.

Fingerprinting can track visitors even if they use anonymizing technologies, such as proxy servers and the Tor network. Other privacy technologies can be easily circumvented to allow tracking, according to Fleischer. Private browsing modes, for example, can be evaded, especially by coordination between sites. And tracking protection lists, a blacklisting technology to block bad actors, are not foolproof either, he said.

Finally, sites that work together can correlate their tracking information to better track visitors.

"By correlating over time and over large networks, sites that are tracking will have better results," he said.

Have a comment on this story? Please click "Add Your Comment" below. If you'd like to contact Dark Reading's editors directly, send us a message.

Comment  | 
Print  | 
More Insights
Register for Dark Reading Newsletters
White Papers
Flash Poll
Current Issue
Cartoon
Video
Slideshows
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2013-6117
Published: 2014-07-11
Dahua DVR 2.608.0000.0 and 2.608.GV00.0 allows remote attackers to bypass authentication and obtain sensitive information including user credentials, change user passwords, clear log files, and perform other actions via a request to TCP port 37777.

CVE-2014-0174
Published: 2014-07-11
Cumin (aka MRG Management Console), as used in Red Hat Enterprise MRG 2.5, does not include the HTTPOnly flag in a Set-Cookie header for the session cookie, which makes it easier for remote attackers to obtain potentially sensitive information via script access to this cookie.

CVE-2014-3485
Published: 2014-07-11
The REST API in the ovirt-engine in oVirt, as used in Red Hat Enterprise Virtualization (rhevm) 3.4, allows remote authenticated users to read arbitrary files and have other unspecified impact via unknown vectors, related to an XML External Entity (XXE) issue.

CVE-2014-3499
Published: 2014-07-11
Docker 1.0.0 uses world-readable and world-writable permissions on the management socket, which allows local users to gain privileges via unspecified vectors.

CVE-2014-3503
Published: 2014-07-11
Apache Syncope 1.1.x before 1.1.8 uses weak random values to generate passwords, which makes it easier for remote attackers to guess the password via a brute force attack.

Best of the Web
Dark Reading Radio
Archived Dark Reading Radio
Marilyn Cohodas and her guests look at the evolving nature of the relationship between CIO and CSO.