ASP.NET machine key


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This SIT is also included in the All credentials bundled SIT.


Symmetric keys in XML configuration.


Various symmetric key formats in XML, for example:

<machineKey decryptionKey="******** </br> 
<machineKey validationKey="********

Credential example

<machineKey validationKey="ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789" decryptionKey="ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789"



SITs that have checksums use a unique calculation to check if the information is valid. This means when the Checksum value is Yes, the service can make a positive detection based on the sensitive data alone. When the Checksum value is No additional (secondary) elements must also be detected for the service to make a positive detection.

Keyword Highlighting


When keyword highlighting is supported in the contextual summary for a sensitive information type or a trainable classifier, in the Contextual Summary view of activity explorer, the keywords in a document that were matched to a policy are highlighted.


This SIT is designed to match the security information that's used to encrypt or hash data in ASP.NET forms authentication and view state.

It uses several primary resources:

  • Patterns of Symmetric key context in xml files.
  • Patterns of CredentialName, CredentialFeatures, AccountIdentityName, AccountIdentityValue, ResourceType, ResourceName.

The patterns are designed to match actual credentials with reasonable confidence. The patterns don't match credentials formatted as examples. Mockup values, redacted values, and placeholders, like credential type or usage descriptions, in the position where an actual secret value should present won't be matched.



  • password
  • key
  • connectionstring