Before revision: U.S. sources have pointed the finger of suspicion at Huawei hardware since at least 2012, suggesting the possibility of the presence of backdoors in Huawei products .
After revision: , without ever providing any evidence to back this claimU.S. sources have pointed the finger of suspicion at Huawei hardware since at least 2012, suggesting the possibility of the presence of backdoors in Huawei products .