The CIA has been attempting to break the security of Apple devices, including the iPhone and iPad, for several years, documents published by The Intercept have revealed.
The Intercept reported uncovering the multi-year campaign after "obtaining documents" chronicling a secret annual "Jamboree" event sponsored by the CIA.
The documents showed that the events have been going on for at least the past decade, and have seen researchers discuss ways to decrypt the firmware on Apple devices.
The research also reportedly investigated possible ways to plant malicious code on Apple devices, and to "seek out potential vulnerabilities in other parts of the iPhone and iPad currently masked by encryption".
The projects also involved the National Security Agency (NSA), and various private sector partners including Lockheed Martin and Sandia National Laboratories.
The CIA, Lockheed Martin and Apple had not responded to V3's request for comment at the time of publishing.
It is unclear how effective the researchers were in cracking Apple's security, but the documents do show that some deployable attack tools were developed.
These included a modified version of Apple's Xcode proprietary software development tool that could be used to "sneak surveillance backdoors into any apps or programs created using Xcode".
If true, the tool could be used to steal passwords and grab messages from infected systems.
Researchers also created a modified OS X updater which could be used to infect Apple desktops with keyloggers that track, record and report what is being typed into infected machines.
The documents show that Apple is one of many technology firms targeted by the CIA. Microsoft's BitLocker encryption system was also discussed during the conferences.
The Intercept's report has been met with caution by members of the security community.
Ken Westin, senior security analyst at Tripwire, said that the leaked documents do not provide vital pieces of information.
"The story provided by The Intercept unfortunately does not tell us a whole lot that most security researchers did not already know or assume," he said.
"The documents they have do not show any evidence of actual successful compromise or active exploits.
"The question arises, however, whether vulnerabilities were discovered that were not disclosed to Apple or other companies whose systems were potentially exploited, as this is where the definition of security research and high-tech espionage diverge."
The CIA is one of many agencies believed to be attempting to break Apple security.
Reports in October 2014 showed that the Chinese government was targeting Apple iCloud customers with sophisticated man-in-the-middle attacks following the local launch of the iPhone 6 and iPhone 6 Plus.
Cook was one of a number of technology leaders to meet US president Barack Obama to discuss the NSA and CIA's surveillance activities in the wake of the PRISM scandal in 2013.
iPhone 8 specs, release date, price, features, basically everything! But will it have a curved display?
But there are three times as many CDOs as there were in 2014
Companies never used to hold big launch events to announce minor upgrades, did they?
Only 35 per cent of IT decision makers regularly review their data formats