Internet Client Vulnerabilities

* Of the numerous techniques to exploit internet end users.

ActiveX

* Microsoft ActiveX

ActiveX Security Model

* Acting within the model described in the previous section malicious programmers could write ActiveX controls to do just about anything they want to a user’s machine. * The thing that stands in the way is the Microsoft’s Authentication paradigm. * Authenticode allows developers to “sign” their code using cryptographic mechanism that can be authenticated by IE and a third party before the code is executed. (VeriSign Corporation is typically the third party)

ActiveX Abuse Countermeasures

* From a developers perspective, don’t write safe-for-scripting controls that could perform privileged actions on a user’s system. * Restrict or disable ActiveX through the use of Microsoft Internet Explorer security zones.

Java

* Created by Sun Micro Systems. * Was created primarily to enable portable, remotely consumable software applications. * Differed from ActiveX in that it included a security ”sandbox” that restrains the programmers from making many of the mistakes that lead to security problems, such as buffer overflows.

Java Countermeasures

* Restrict Java trough the use of Microsoft Internet Explorer security zones. * Non-IE consult documentation on how to restrict.

JavaScript and Active Scripting

* Originally “LiveScript” and is still associated with Sun’s Java, but is actually a separate scripting language created by Netscape. * Blend of Perl- like ease-of-use with c/c++ like power.

JavaScript Countermeasures

* Restrict JavaScript and Active Scripting trough the use of Microsoft Internet Explorer security zones.

Cookies

* Underlies the World Wide Web, allows for tracking things from one visit to another. * Cookies, or special tokens contained with in HTTP requests and responses, that allow websites to remember who you are from visit to visit. * Attackers who get their hands on your cookies might be able to spoof your online identity or glean sensitive information. * The brute-force way to hijack cookies is to sniff them off the network and then replay them to the server.

* Get a tool to manage cookies. * IE’s cookie screening feature. * Use SSL. * Disable cookies.

Cross-Site Scripting (xss)

* XXS typically results from a web application that takes input from one user and displays it to another user.

SSL Attacks

* Based on public-key cryptography. * SSL is a security implementation, and as such it is open to interpretation by those who implement it. * IMPLEMENTATION flaws can reduce the security of any specification to zero.

SSL Countermeasures

* Keep your Internet Client software fully updates and patched. * Verify the SSL certificate.

E-mail Hacking

* Single most effective avenue into the computing space of the internet user. * Becomes a very powerful attack when embedded with ActiveX, JavaScript and is extended with its own powerful capabilities, such as file attachments.

File Attachments

* One of the most convenient features of e-mail is the ability to attach files. * This can be used to deliver executable payloads directly to a end users desktop. * Greatest single vector of attack since the beginning. * Disguising executables as MP3’s or other file types.

MIME

* Underlying e-mail attachments also played a significant role in the history of client hacking. * Multipart Internet Mail Extensions (MIME)is the standard for attaching files to e-mail messages by breaking them in to manageable chunks and Base64-encoding.

E-mail Hacking Countermeasures

* Keep our software up to date. * Don’t open e-mail from people you don’t know or a chain forward. * Disable ActiveX and JavaScript for e-mail.

General Microsoft Client-Side Countermeasures

* Deploy a personal firewall. * Keep up to date on all software patches. * Run antivirus software. * Run with least privilege. * Administrators should run the mentioned software at choke points. * Read e-mail in plain text. * Configure office productivity programs as securely as possible. * Don’t be gullible. * Keep your computing devices physically secure.

Malware

* Includes.

Countermeasures

* Always back up your system before you have any problems. * Clean it up with the appropriate tools.

* The book recommends.

* I recommend.

Quiz

1 What was Microsoft's answer to Java? ActiveX

2 Who created JavaScript? Netscape

3 What is the protocol over which the majority of e-commerce transactions occur? SSL

4 5 What are 3 of the General Microsoft Client-Side Countermeasures?

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