The Israeli company stands accused of developing an exploit that allowed surveillance malware to be delivered to the phones of 1,400 individuals via WhatsApp.
NSO Group contested the lawsuit on the grounds it is a contractor of foreign states - including the Kingdom of Bahrain, the United Arab Emirates and Mexico - which the company said gave it immunity from legal penalty.
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However, US District Judge Phyllis Hamilton found in favor of WhatsApp, squashing the appeal over NSO Group’s inability to sufficiently argue and evidence its case.
The judge did, however, agree that WhatsApp should not be allowed to pursue the claim that NSO Group tampered with its servers.
WhatsApp spyware lawsuit
The case of WhatsApp vs. NSO Group first came to light in October, after the company uncovered evidence to suggest the Israeli firm was behind the spyware attack.
The attack itself exploited an audio-calling vulnerability in the app. Targeted users - including over 100 human rights defenders and journalists - appeared to receive a call, but were instead infected with malware that handed its operators complete access to the device.
WhatsApp was able to patch the vulnerability quickly and subsequently issued a filing that claimed NSO Group “developed their malware in order to access messages and other communications after they were decrypted [on target devices]”.
The company was later handed a boost in March, when NSO Group failed to attend a hearing at the Northern District of Court of California. In response to the defendant’s failure to attend court, a default notice was issued that could have resulted in an automatic judgement in favor of WhatsApp, although this was later batted away.
The Facebook-owned company has celebrated the outcome of the most recent appeal and will now carry the case forward as originally planned.
“The decision also confirms that WhatsApp will be able to obtain relevant documents and other information about NSO’s practices,” noted a WhatsApp spokesperson.
The case is the first of its kind to see a service provider sue a third party on behalf of its customers, so will continue to be followed with interest.
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