For TCAS II systems using transponders compliant with MOPS earlier than RTCA DO-181F, an attacker can impersonate a ground station and issue a Comm-A Identity Request. This action can set the Sensitivity Level Control (SLC) to the lowest setting and disable the Resolution Advisory (RA), leading to a denial-of-service condition.
Weakness
One or more system settings or configuration elements can be externally controlled by a user.
Potential Mitigations
- Compartmentalize the system to have “safe” areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area.
- Ensure that appropriate compartmentalization is built into the system design, and the compartmentalization allows for and reinforces privilege separation functionality. Architects and designers should rely on the principle of least privilege to decide the appropriate time to use privileges and the time to drop privileges.
References