### AWS IAM Virtual MFA Device Registration Attempt with Session Token
- rule change kql to eql so that I could use startsWith function instead of wildcard for the `ASIA*`, temporary session determination.
- there is a known false positive for rules like this. When you login to the AWS console, a temporary session token is created in the back-end so in cloudtrail the token id looks the same (`ASIA*`) as temporary session tokens created by actions like `GetSessionToken` or `AssumeRole`, which is what this rule meant to capture. Our current data source does now allow us to distinguigh between these type of events. However, cloudtrail does provide a field `sessionCredentialFromConsole:true` that I am putting in a request for Integrations to include. This would allow us to exclude Console login sessions from rules like this that look for temporary token abuse.
- reduced execution window
- updated description, FP and IG
- update MITRE mapping
- added highlighted fields
AWS IAM Deactivation of MFA Device
- removed `DeleteVirtualMFADevice` from the scope of this rule. When Deleting an MFA device you must deactivate it first if it is associated with a user. You can also Create an MFA device and then Delete it without it being activated for a particular user. By capturing both Deactivation and Deletion events we have duplicate alerts for the same activity (This duplication of events is seen in telemetry.) We also capture benign instances where un-used MFA devices are deleted (which is a clean-up best practice). By reducing the scope to only `DeactivateMFADevice` actions, we capture the most threat-centric behavior which should be investigated.
- reduced execution window
- updated Description, FP and IG
- added highlighted fields
Isai
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