HttpOnly

Browsers Supporting HTTPOnly

Using WebGoat's HTTPOnly lesson, the following web browsers have been tested for HTTPOnly capabilities. The results are listed below in table 1.

Table 1: Browsers Supporting HTTPOnly

Browser	Version	Supports HTTPOnly?
Microsoft Internet Explorer	6 (SP1) - 7	Partially*
Mozilla Firefox	2.0.0.5	Partially*
Netscape Navigator	9.0b2	No
Opera	9.22	No

• An attacker could still access the session identifier cookie using a XmlHttpRequest.

Using WebGoat to Test for HTTPOnly Capabilities

Getting Started

Assuming you have already installed and launched WebGoat, begin by navigating to the ‘HTTPOnly Test’ lesson located within the Cross-Site Scripting (XSS) category. After selecting the ‘HTTPOnly Test’ link, as shown below in figure 1, you are now able to begin testing web browsers that support HTTPOnly.

Figure 1 - Accessing WebGoat's HTTPOnly Test Lesson

Lesson Goal

If the HTTPOnly flag is set, then your browser should not allow client-side script to access the cookie. Unfortunately, since the attribute is relatively new, several browsers neglect to handle the new attribute properly.

The purpose of this lesson is to test whether your browser supports the HTTPOnly cookie flag. Note the value of the unique2u cookie. If your browser supports HTTPOnly and you enable it for a cookie, client side code should NOT be able to read OR write to that cookie, but the browser can still send its value to the server. However, some browsers only prevent client side read access, but do not prevent write access.

Testing Web Browsers for HTTPOnly Support

The following test was performed on two browsers, Internet Explorer 7 and Opera 9.22, to demonstrate the results when the HTTPOnly flag is enforced properly. As you will see, IE7 properly enforces the HTTPOnly flag, whereas Opera does not properly enforce the HTTPOnly flag.

  1) Begin by selection the option to turn HTTPOnly off as shown below in figure 2.

Figure 2 - Disabling HTTPOnly

  2) After turning HTTPOnly off, select the “Read Cookie” button. 

An alert dialog box will display on the screen notifying you that since HTTPOnly was not enabled, the ‘unique2u’ cookie was successfully read as shown below in figure 3.