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

instruction contained an

expires

attribute with a date that is in the future, this will cause the

browser to persist that cookie until that date. For example:

UID=d475dfc6eccca72d0e expires=Wed, 12-Mar-08 16:08:29 GMT; 

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If a persistent cookie is set that contains any sensitive data, then a local

attacker may be able to capture this data. Even if a persistent cookie con-

tains an encrypted value, if this plays a critical role such as reauthenticat-

ing the user without entering credentials, then an attacker who captures

it will be able to resubmit it to the application without actually decipher-

ing its contents (see Chapter 6).

Cached Web Content

Most browsers cache non-SSL web content unless a web site specifically

instructs them not to. The cached data is normally stored on the local file system.

HACK STEPS

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