Important changes to CloudTrail events for AWS IAM Identity Center

AWS IAM Identity Center is making important changes to its CloudTrail events, effective January 13, 2025, to simplify user identification and enhance security:

• Will stop emitting `userName` and `principalId` fields in user identity elements
• Will replace these fields with `userId` and `identityStoreArn`
• Will change `userIdentity` type from `Unknown` to `IdentityCenterUser` for authenticated users
• Will emit `credentialId` to help track user actions within a session
• Will hide group `displayName` in administrative events, replacing it with "HIDDEN_DUE_TO_SECURITY_REASONS"

These changes affect CloudTrail events for AWS access portal, OIDC, sign-in, and Identity Store events. AWS recommends updating workflows that rely on these fields before the January 13, 2025 implementation date.