Whatsapp urges users to update app after cyber surveillance attack

Whatsapp is encouraging users to update to the latest version of the app after discovering a vulnerability that allowed spyware to be injected into a user’s phone through the app’s phone call function.

WhatsApp, which is owned by Facebook, said the attack targeted a "select number" of users, and was orchestrated by "an advanced cyber actor".

The spyware was developed by the Israeli cyber intelligence company NSO Group, according to the Financial Times, which first reported the vulnerability.

Attackers could transmit the malicious code to a target’s device by calling the user and infecting the call whether or not the recipient answered the call. Logs of the incoming calls were often erased, according to the report.

WhatsApp said that the vulnerability was discovered this month, and that the company quickly addressed the problem within its own infrastructure. An update to the app was published Monday, and the company is encouraging users to upgrade out of an abundance of caution.

The company has also alerted US law enforcement to the exploit, and published a “CVE notice”, an advisory to other cybersecurity experts alerting them to “common vulnerabilities and exposures”.

The vulnerability was used in an attempted attack on the phone of a UK-based attorney on 12 May, the FT reported. The lawyer, who was not identified by name, is involved in a lawsuit against NSO brought by a group of Mexican journalists, government critics and a Saudi Arabian dissident.

“The attack has all the hallmarks of a private company reportedly that works with governments to deliver spyware that takes over the functions of mobile phone operating systems,” WhatsApp said in a statement. “We have briefed a number of human rights organizations to share the information we can and to work with them to notify civil society.”

WhatsApp has about 1.5bn users around the world. The messaging app uses end-to-end encryption, making it popular and secure for activists and dissidents. The Pegasus spyware does not affect or involve the app’s encryption.