SAML: Why does the objectGUID of a user in Mattermost differ from what we’re seeing in ADFS?

Understanding Active Directory objectGUID Formats

The Active Directory objectGUID attribute (LDAP display name: objectGUID) is a 16-byte array that can be displayed in multiple formats depending on the tool or environment you're using.

Common Representations

• Linux (ldapsearch / LDIF format)
  Displays objectGUID as Base64:
  Hrz/HqNKnU+lCNTYHx9Ycw==
• Golang (via go-ldap/ldap)
  Displays objectGUID as a hexadecimal array with backslashes:
  \1e\bc\ff\1e\a3\4a\9d\4f\a5\08\d4\d8\1f\1f\58\73
  
  You can remove the backslashes to get:
  1ebcff1ea34a9d4fa508d4d81f1f5873
  
  This can be parsed using Golang to output base-10 values:
  30 188 255 30 163 74 157 79 165 8 212 216 31 31 88 115
• Windows PowerShell
  Displays objectGUID in GUID format:
  1effbc1e-4aa3-4f9d-a508-d4d81f1f5873