The acting head of the U.S. Department of Homeland Security said the agency was assessing the cyber risk of smart TVs sold by the Chinese electronics giant TCL, following reports last month in The Security Ledger and elsewhere that the devices may give the company “back door” access to deployed sets.
Speaking at The Heritage Foundation, a conservative think tank, Acting DHS Secretary Chad Wolf said that DHS is “reviewing entities such as the Chinese manufacturer TCL.”
“This year it was discovered that TCL incorporated backdoors into all of its TV sets exposing users to cyber breaches and data exfiltration. TCL also receives CCP state support to compete in the global electronics market, which has propelled it to the third largest television manufacturer in the world,” Wolf said, according to a version of prepared remarks published by DHS. His talk was entitled “Homeland Security and the China Challenge.”
As reported by The Security Ledger last month, independent researchers John Jackson, (@johnjhacking) -an application security engineer for Shutter Stock – and a researcher using the handle Sick Codes (@sickcodes) identified and described two serious software security holes affecting TCL brand television sets. The first, CVE-2020-27403, would allow an unprivileged remote attacker on the adjacent network to download most system files from the TV set up to and including images, personal data and security tokens for connected applications. The flaw could lead to serious critical information disclosure, the researchers warned.
The second vulnerability, CVE-2020-28055, would have allowed a local unprivileged attacker to read from- and write to critical vendor resource directories within the TV’s Android file system, including the vendor upgrades folder.
Both flaws affect TCL Android Smart TV series V8-R851T02-LF1 V295 and below and V8-T658T01-LF1 V373 and below, according to the official CVE reports. In an interview with The Security Ledger, the researcher Sick Codes said that a TCL TV set he was monitoring was patched for the CVE-2020-27403 vulnerability without any notice from the company and no visible notification on the device itself.
In a statement to The Security Ledger, TCL disputed that account. By TCL’s account, the patched vulnerability was linked to a feature called “Magic Connect” and an Android APK by the name of T-Cast, which allows users to “stream user content from a mobile device.” T-Cast was never installed on televisions distributed in the USA or Canada, TCL said. For TCL smart TV sets outside of North America that did contain T-Cast, the APK was “updated to resolve this issue,” the company said. That application update may explain why the TCL TV set studied by the researchers suddenly stopped exhibiting the vulnerability.
While TCL denied having a back door into its smart TVs, the company did acknowledge the existence of remote “maintenance” features that could give its employees or others control over deployed television sets, including onboard cameras and microphones. Owners must authorize the company to access cameras and microphones, however, according to a company statement.
The company did not address in its public statements the question of whether prior notification of the update was given to TCL owners or whether TV set owners were given the option to approve the update before it was installed.
Sick Codes, in a phone interview with The Security Ledger, said the company’s ability to push and update code to its deployed sets without owner approval amounted to a back door that could give TCL access to audio and video streams from deployed sets, regardless of the wishes of owners.
“They can update the application and make authorization happen through that. They have full control,” he said.
Such concerns obviously raised alarms within the Department of Homeland Security as well, which has taken steps to ban technology from other Chinese firms from use on federal networks.
In his address on Monday, Acting Secretary Wolf said the warning about TCL will be part of a a broader “business advisory” cautioning against using data services and equipment from firms linked to the People’s Republic of China (PRC).
This advisory will highlight “numerous examples of the PRC government leveraging PRC institutions like businesses, organizations, and citizens to covertly access and obtain the sensitive data of businesses to advance its economic and national security goals,” Wolf said.
“DHS flags instances where Chinese companies illicitly collect data on American consumers or steal intellectual property. CCP-aligned firms rake in tremendous profits as a result,” he said.
The statement is part of escalating tensions between Washington and Beijing. On Friday, Commerce Secretary Wilbur Ross announced export controls on 77 Chinese companies including the country’s biggest chipmaker, SMIC, and drone maker DJI that restrict those firms’ access to US technology. The order cites those firms alleged ties to China’s military.
TCL did not respond to an email request for comment prior to publication of this story. We will update this story as more information becomes available.
Editor’s note: this story was updated to add reference to John Jackson, who helped discover the TCL vulnerabilities. – PFR 12/22/2020