US intelligence service leaders have repeated claims of Huawei collaborating with the Chinese government since 2012, but have provided no evidence.

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Government pressure axed a deal for Huawei's Mate 10 Pro from being carried by AT&T and Verizon.

Despite repeated claims, neither the government nor third party researchers have provided evidence of an extant backdoor in Huawei products.

In testimony to the Senate Intelligence Committee on Tuesday, six US intelligence chiefs, including FBI Director Christopher Wray and CIA Director Mike Pompeo, again cautioned against buying products or using services from Huawei or ZTE.

Wray provided this rationale:

We're deeply concerned about the risks of allowing any company or entity that is beholden to foreign governments that don't share our values to gain positions of power inside our telecommunications networks. That provides the capacity to exert pressure or control over our telecommunications infrastructure. It provides the capacity to maliciously modify or steal information. And it provides the capacity to conduct undetected espionage.

This caution follows the last minute cancellation of plans for AT&T and Verizon to sell Huawei phones in the US. Acording to Reuters, the deal was terminated at the behest of "some members of Congress" who "lobbied against the idea with federal regulators." The Mate 10 Pro was planned for carrier launch in the US, with an advertising campaign featuring Gal Gadot.

Huawei is currently the third-largest phone manufacturer worldwide, though in the US, the highest profile phone available is the now-discontinued Nexus 6P, which is available only as an unlocked, off-contract phone. The firm was founded in 1987 as a manufacturer of telephone switching equipment, an industry that remains its core business.

While Huawei is now a major manufacturer of smartphones, the company only entered that market in 2012. The company is producing equipment for future 5G mobile network rollouts, tests of which have been performed in the US with the cooperation AT&T. This is also reportedly a point of contention, with pressure being applied to the telecom to end this collaboration as well.

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This distribution deal was seemingly planned for announcement at CES in January. Richard Yu, the CEO of Huawei's consumer products division gave a pointed speech about the situation, noting that "Everybody knows that in the US market that over 90 percent of smartphones are sold by carrier channels," and that "It's a big loss for us, and also for carriers, but the more big loss is for consumers, because consumers don't have the best choice in the market."

The Mate 10 Pro is still planned for sale in the US as an unlocked phone available via online retailers, though this has also had a rocky start as the product page at Best Buy was filled with glowing reviews, despite the phone not yet being available stateside.

The criticisms levied against Huawei are not new, but this is one that bears more than a passing resemblance to a conflict of interest, if not outright economic protectionism. In 2013, former NSA chief Gen. Michael Hayden stated that Huawei had engaged in espionage on behalf of China. At the time, Hayden was on the board of Motorola Solutions, a competitor of Huawei. Two years prior, Motorola Solutions paid an undisclosed sum to Huawei to settle an intellectual property dispute.

Despite these claims, no evidence has ever been produced by the government or independent security researchers to indicate that a Huawei product includes a backdoor. Given the mass-market nature of smartphones--and the community of hackers and custom ROM developers in the Android scene--the likelihood that one could be concealed particularly well is suspect. However, cellular modems are basically black boxes which are designed to resist external tampering to prevent users from performing actions which may degrade service for other users on the network. Similarly, commercial-grade networking equipment from any vendor are not particularly open, and this attribute lends itself to conspiracy theories.

Documents disclosed by former NSA contractor Edward Snowden indicated that Huawei has been the target of a covert surveillance program since 2007. One operation, called "Shotgiant," sought to find any link between the company and the People's Liberation Army.

Additionally, the NSA has targeted commercial networking equipment sold by Huawei, as "many of our targets communicate over Huawei produced products, we want to make sure that we know how to exploit these products," according to one leaked document. According to the original reporting by Der Spiegel, none of the leaked documents indicated if any links were found, nor have any vulnerabilities (either intentional backdoors or vulnerabilities introduced as a design flaw or oversight) been discovered.

Update: Representatives from Huawei and ZTE have separately provided statements to TechRepublic about this story.

Huawei:

Huawei is aware of a range of U.S. government activities seemingly aimed at inhibiting Huawei's business in the U.S. market. Huawei is trusted by governments and customers in 170 countries worldwide and poses no greater cybersecurity risk than any ICT vendor, sharing as we do common global supply chains and production capabilities. We are committed to openness and transparency in everything we do. Ultimately, Huawei will continue to develop its global business through a significant commitment to innovation and R&D and to delivering technology that helps our customers succeed in all markets that value the innovation and value it delivers.

ZTE:

"ZTE is proud of the innovation and security of our products in the US market. As a publicly traded company, we are committed to adhering to all applicable laws and regulations of the United States, work with carriers to pass strict testing protocols, and adhere to the highest business standards. Our mobile phones and other devices incorporate US-made chipsets, US-made operating systems and other components. ZTE takes cybersecurity and privacy seriously and remains a trusted partner to our US suppliers, US customers and the people who use our high quality and affordable products for their communications needs."

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