Mass ROPC Enumeration Burst With Blank App Name Correlated to Account Lockout Spike
Detects a high-volume burst of ROPC (Resource Owner Password Credentials) sign-in attempts using a spoofed/unregistered OAuth client ID, identified by a populated Application ID field paired with a blank Application Name field, targeting a single account within a short window. This enumeration pattern has been observed to correlate with mass account lockouts across an organization.
Sigma
