Short-selling firm Muddy Waters says in a legal filing that outside experts validate its claims that St. Jude Medical cardiac implants are vulnerable to potentially life-threatening cyber attacks.
Muddy Waters released a 53-page report from cyber security firm Bishop Fox as part of a legal filing in federal court in Minnesota in its defence against a suit brought by St. Jude.
Bishop Fox said in the report validated the claims with help from well-known specialists in cryptography, computer hardware hacking, forensics and wireless communications, and cyber research firm MedSec Holdings that St. Jude cardiac implants are susceptible to hacking.
The report said the wireless communications in St. Jude cardiac devices are vulnerable to hacking, making it possible for hackers to convert the company's Merlin@home patient monitoring devices into "weapons" that can cause cardiac implants to stop providing care and deliver shocks to patients.
Bishop Fox said it conducted successful test attacks from 3 meters away, but that the range might be extended to as far as 30 meters with an antenna and a specialised device known as a software defined radio.
St. Jude has strongly disputed those claims, which are under investigation by the US Food and Drug Administration.
One of the world's biggest makers of implantable cardiac devices, St. Jude filed a lawsuit against San Francisco-based Muddy Waters, Miami-based MedSec and individuals affiliated with those firms.
St. Jude accused them of intentionally disseminating false information about its heart devices to manipulate its stock price, which fell five per cent the day they went public with their claims.
The FDA said in a statement it had no comment on the litigation but that based on information obtained to date it urged patients to continue using devices as directed by their physicians.
"The benefits of the devices far outweigh any potential cyber security vulnerabilities," the FDA said.
Short sellers like Muddy Waters make bets that stock prices will fall, selling borrowed shares so they can buy them at a lower price and profit from the difference.
