View State snooping
Summary: PortSwigger Research surveyed more than 10,000 internet-facing ASP.NET applications and found the largest ViewState at 3.8Mb, in a government web application displaying tables of statistics. The survey also found a surprising number of applications not using the EnableViewStateMac option, which is now set by default in ASP.NET, and noted that even with it set, users can decode and read ViewState contents when it is not encrypted.
What you should know: Without EnableViewStateMac, a user can modify ViewState contents and potentially affect how the application processes requests, and unencrypted ViewState can be decoded and read by anyone - including developers who store arbitrary data in it beyond the default serialization of UI controls.
Read the original at PortSwigger Research ↗
- Topics
- Vulnerabilities & Patching
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