JWT Algorithm Confusion Attack Detection
Detects potential JSON Web Token (JWT) algorithm confusion attacks. This occurs when an attacker sends a token signed with a symmetric algorithm (e.g., HS256) to a server expecting an asymmetric one (e.g., RS256). If the server is misconfigured, it may use its public key as the HMAC secret, allowing the attacker to forge valid tokens. The rule specifically looks for JWTs with symmetric HMAC-based algorithms (HS256, HS384, HS512) being sent to applications configured to exclusively use asymmetric key algorithms.
Microsoft Sentinel (KQL)

