Indian Scout 2025: WCM brute-force lockout abused for persistent denial-of-service

Uncontrolled resource consumption in the Wireless Control Module (WCM) of the Indian Motorcycle Scout Bobber + Tech 2025 model year allows an adjacent-network attacker with write access to the in-vehicle network to permanently immobilize the motorcycle. The WCM enforces a brute-force lockout on the immobilizer authentication algorithm, but the lockout counter is reachable by any unauthenticated message, has no session binding, and does not reset on power cycle. An attacker can deliberately trip the lockout with a small number of crafted frames, leaving the bike un-startable until dealer service.

Specific thresholds have been withheld pending vendor remediation.

Recommended remediation:

Bind the brute-force counter to an authorized WCM-to-ECM session token, rate-limit on a sliding window, and provide an owner-recoverable unlock path (e.g., PIN re-entry at the Digital Round) instead of dealer-only recovery.

Scott Sheahan, Rustic Security LLC (finder)

2025-03-26: Reported to Indian Motorcycle (Polaris Inc.) by Rustic Security LLC under responsible disclosure

2026-05-29: Public disclosure by ASRG