Court documents indicate FBI may be able to access Signal messages on locked iPhone device

Court documents included screenshots of Signal messages: "There's also some metadata in the screenshots, which indicates not only that Signal had been decrypted on the phone, but that the extraction was done in 'partial AFU,'" Forbes reported.
Signal logo in App Store seen on screen in illustration photo

Court documents reportedly indicate that the FBI may have the capability to gain access to texts within an app called Signal on a locked iPhone device.

"The clues came via Seamus Hughes at the Program on Extremism at the George Washington University in court documents containing screenshots of Signal messages between men accused, in 2020, of running a gun trafficking operation in New York," Forbes reported. 

"There's also some metadata in the screenshots, which indicates not only that Signal had been decrypted on the phone, but that the extraction was done in 'partial AFU,'" the outlet noted. "That latter acronym stands for 'after first unlock' and describes an iPhone in a certain state: an iPhone that is locked but that has been unlocked once and not turned off. An iPhone in this state is more susceptible to having data inside extracted because encryption keys are stored in memory. Any hackers or hacking devices with the right iPhone vulnerabilities could then piece together keys and start unlocking private data inside the device."

The device "appears to be either an iPhone 11 (whether Pro or Max) or a second generation iPhone SE," Forbes reported, noting that it is not clear which software version was installed on the device or whether authorities can gain access to private information on an iPhone 12, the latest models of the popular smartphone line.

"If someone is in physical possession of a device and can exploit an unpatched Apple or Google operating system vulnerability in order to partially or fully bypass the lock screen on Android or iOS, they can then interact with the device as though they are its owner," a Signal spokesperson said, according to Forbes. "Keeping devices up-to-date and choosing a strong lock screen passcode can help protect information if a device is lost or stolen."