Security expert Yossi Appleboum, who serves as co-CEO of Sepio Systems, provided documents, analysis and other evidence to suggest that a major U.S. telecommunications company found manipulated hardware from Super Micro Computer Inc. in its network and removed it in August, Bloomberg News reported Oct. 9.

While spokespersons representing AT&T Inc., Sprint Corp. and Verizon Communications Inc. said the carriers were not affected by the alleged hacking, T-Mobile US Inc. has yet to comment. Bloomberg could not disclose the name of the company because of Appleboum's nondisclosure agreement with the telecom.

"We still have no knowledge of any unauthorized components and have not been informed by any customer that such components have been found," Super Micro said in a statement. "We are dismayed that Bloomberg would give us only limited information, no documentation, and half a day to respond to these new allegations."

An Apple Inc. information security executive recently denied to Congress that any of its hardware was compromised in an alleged 2015 incident described in an Oct. 4 Bloomberg Businessweek report.

Shares in Super Micro Computer plunged to record lows during the week ended Oct. 5, after a report alleged that Chinese spies infiltrated some of the company's data servers, which were then distributed to tech giants Apple and Amazon.com Inc. Super Micro, Apple and Amazon have all strongly denied the claims asserted in the article.