TCAS II Impersonation Vulnerability Leading to Denial-of-Service

A vulnerability exists in TCAS II systems with transponders compliant with MOPS prior to RTCA DO-181F. An attacker can impersonate a ground station and send a Comm-A Identity Request, which can lower the Sensitivity Level Control (SLC) and disable the Resolution Advisory (RA). This manipulation creates a denial-of-service condition by disrupting normal collision avoidance operations.

Impact

Exploitation of this vulnerability can cause a denial-of-service condition by disabling critical collision avoidance alerts, potentially leading to unsafe flight situations.

Remediation

To mitigate this vulnerability, TCAS II systems should be upgraded to ACAS X or the associated transponder should be updated to comply with RTCA DO-181F.