In the early evening of March 5, 2012, in Cairo, Egyptian revolutionaries stormed the headquarters of the secret police called the State Security Investigations (SSI) service, a building known as “the capital of hell” because of its reputation as a place where ruthless officers tortured prisoners.
Inside, protesters found both intact and shredded documents, torture devices, hard drives, and CDs, and DVDs — all documenting nightmarish torture and widespread surveillance.
Among the documents, protesters found a memorandum written in Arabic by SSI officers about a mysterious software called FinFisher, made by the British-German company Gamma International.
The officers reported that FinFisher was a “high-level hacking system” with several capabilities, including the ability to access email inboxes, to upload “spy files” on the target’s device, tracking their communications, gaining “complete control” over the devices of the hacked targets, and — crucially — documenting their “success in hacking” people’s accounts on Skype network, which was billed as the “most secure method of communication” because Skype is encrypted.
In the early 2010s, Skype was the most popular internet phone calling app in the world, and not just in Egypt.
Launched in 2003, Skype promised its users unprecedented privacy, with calls “highly secure with end-to-end encryption,” which — in theory — made it impossible for internet hackers or spies to read the chats and listen in on calls while they traveled across the internet. That’s why Egyptians spies needed to hack directly into people’s computers with FinFisher to listen in on their targets’ Skype calls.
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“Skype calls have excellent sound quality and are highly secure with end-to-end encryption,” Skype’s homepage read in 2004.
Skype’s encryption was a revolutionary and groundbreaking feature at the time. In the mid-1990s, legendary cryptographer Phil Zimmermann created Pretty Good Privacy, or PGP, software that allowed people to make files or emails private with end-to-end encryption, meaning only the sender and receiver could read the content of the message. But PGP was clunky and wasn’t included in easy-to-use chat and calling apps.
Now, more than 20 years later, end-to-end encryption is baked into apps that are used by billions of people, most of whom may not realize their messages and calls are secured with this data-scrambling technology. Apple’s iMessage and FaceTime, Facebook Messenger, Signal, and WhatsApp, among others, are all end-to-end encrypted by default.
But in 2003, Skype was the first one to offer this level of encryption and privacy.
After it launched, Skype sparked anger among law enforcement agencies all over the world. In Italy, the Polizia Postale (Postal and Communications Police), the agency tasked with investigating crimes on the internet, asked the small cybersecurity consulting startup Hacking Team to build phone spyware capable of getting around Skype’s encryption, among other snooping features, according to former Hacking Team employees who have I have spoken with.
Across the world, other governments found different ways to spy on Skype users. In 2008, Citizen Lab, a digital rights research group at the University of Toronto, found that Skype had been modified to allow Chinese spies to collect messages exchanged across the service. In China, Skype was operated by Tom-Skype, a joint venture between a Chinese wireless operator and eBay, which owned Skype at the time.
Years later, secret files leaked by former U.S. government contractor Edward Snowden revealed that Microsoft, which now owns Skype, had modified the app to allow the National Security Agency and other authorities to collect calls and messages, effectively defeating the app’s vaunted encryption.
This week, Microsoft announced that it will shut down Skype on May 5. At this point, Skype is a fringe app. In 2023, Microsoft said it still had 36 million users, a far cry from its peak of 300 million users.
While Skype is largely a relic of yesteryear and will soon stop operating, Skype’s legacy lives on in the technology that secures the communications of all of the world’s most popular chat apps. And the world is a safer, freer place, thanks to Skype’s original developers’ groundbreaking ideas about privacy.
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