This paper examines operation of TFRC (TCP-Friendly Rate Control) in scenarios where the receiver is untrustworthy and can misbehave to receive data at an unfairly high rate at the expense of competing traffic. Several attacks are considered for a selfish receiver to take advantage of TFRC. After confirming experimentally that the identified receiver attacks are effective, we design Robust TCP-Friendly Rate Control (RTFRC), a TFRC variant resilient to the attacks. We also show that additional attacks targeted directly at RTFRC are unable to compromise the protocol.