Apple issued a security update on Wednesday for all its operating systems to patch dangerous vulnerabilities that could allow attackers to take over someone’s entire device.

The vulnerabilities in question, first revealed on June 1, appeared to have led the main Russian intelligence agency to make unusually public claims that Apple intentionally left the flaws in its iOS so the National Security Agency and other U.S. entities could compromise “thousands” of iPhones in Russia. Apple has denied those claims.

The charges from the Federal Security Service, or FSB, came the same day that researchers with cybersecurity firm Kaspersky published a report detailing what they said was an “ongoing” zero-click iMessage exploit campaign dubbed “Operation Triangulation” targeting iOS that allowed attackers to run code on phones with root privileges, among other capabilities. Kaspersky published an additional analysis Wednesday, saying that after roughly six months of collecting and analyzing the data, “we have finished analyzing the spyware implant and are ready to share the details.”