The Independent reports that U.K. investigators have successfully retrieved the final message sent by terrorist attacker Khalid Masood using the encrypted messaging service WhatsApp.
The message was a declaration that Masood was waging jihad as retribution for Western interventions in Muslim countries.
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Security agencies had sought to retrieve the message to establish what motivated Masood, also known as Adrian Ajao, to kill five and injure 50 when he drove a car through crowds on Westminster Bridge in London. It was hoped that the message, sent two minutes before the attack began, could help determine whether he was communicating with a terrorist network.
Following Masood’s attack, U.K. Home Secretary Amber Rudd described WhatsApp’s encryption tools as “completely unacceptable,” and called for technology services to allow governments to access encrypted user data for use in fighting terrorism. Security experts broadly resist any such “back door,” saying that it would inevitably be targeted by malicious hackers, including the cyberwarfare forces of hostile governments.
Masood’s WhatsApp message does not seem to have revealed direct ties to any terrorist network. The recipient of the message was reportedly questioned and released by police and security agencies, who concluded that he was not involved in or aware of Masood’s plans. That suggests Masood may have been acting independently, though ISIS has claimed credit for the attack.
It is unclear whether security forces actually penetrated WhatsApp’s encryption when retrieving Masood’s message. According to the Independent, the message could be retrieved because authorities had Masood’s phone, and security sources said the message was accessed using “human and technical intelligence.” That suggests they may have simply accessed Masood’s WhatsApp messages using his passwords.
However, the Daily Mail found that Masood’s WhatsApp profile has not been active since the attack. The Mail infers that’s a sign that his account was not accessed through his phone, though it's questionable whether simply opening the app would be shown as profile activity.
Whatever their method, authorities claimed to the Independent they now have the technical ability to repeat the process in the future.
WhatsApp, which was acquired by Facebook for $19 Billion in 2014, has more than 1 billion users worldwide. The service has highly touted its end-to-end encryption since it began deploying the feature in 2014, saying that “privacy and security is in our DNA.” WhatsApp cofounder Jan Koum frequently cites his experience growing up in the surveillance-heavy USSR as motivation for protecting users' data.