The Web Application Hacker’s Handbook Discovering and Exploiting Security Flaws

Use of Public Information

There may be content and functionality within the application that is not

presently linked from its main content, but has been linked in the past. In this

situation, it is likely that various historical repositories will still contain refer-

ences to the hidden content. There are two main types of publicly available

resources that are useful here:

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Search engines

such as Google, Yahoo and MSN. These maintain a 

fine-grained index of all content which their powerful spiders have 

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Chapter 4 

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Mapping the Application

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discovered, and also cached copies of much of this content, which per-

sists even after the original content has been removed.

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Web archives

such as the WayBack Machine located at

web.archive.org

. These archives maintain a historical record of a very

large number of web sites, and in many cases allow users to browse a

fully replicated snapshot of a given site as it existed at various dates

going back several years.

In addition to content that has been linked in the past, these resources are

also likely to contain references to content that is linked from third-party sites,

but not from within the target application itself. For example, some applica-

tions contain restricted functionality for use by their business partners. Those

partners may disclose the existence of the functionality in ways that the appli-

cation itself does not.

HACK STEPS

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