We have a few scenarios which mean users can see other users data if they're on the same machine.
Scenario 1
Login User A
Browse to forms with perosnal data
Logout User A
Login User B
Either hit back button until you reach User A's personal data or..
Use browser history to jump directly to user A's personal data.
Scenario 2
Login User A
Browse to forms with personal data
Close browser
New Browser, Use history to go directly to User A's data.
The 2nd one was caused by the browser displaying the page from its cache, so for that one, I added the following to the web.config..
<caching>
<outputCache enableOutputCache="false" enableFragmentCache="false" sendCacheControlHeader="false" omitVaryStar="false" />
</cachi ...
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