Communications Backdoor in Chinese Power Inverters

> U.S. energy officials are reassessing the risk posed by Chinese-made devices that play a critical role in renewable energy infrastructure after unexplained communication equipment was found inside some of them, two people familiar with the matter said.
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> Over the past nine months, undocumented communication devices, including cellular radios, have also been found in some batteries from multiple Chinese suppliers, one of them said.
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> Reuters was unable to determine how many solar power inverters and batteries they have looked at.
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> The rogue components provide additional, undocumented communication channels that could allow firewalls to be circumvented remotely, with potentially catastrophic consequences, the two people said.

The article is short on fact and long on innuendo. Both more details and credible named sources would help a lot here.