Cicada 3301: who made the internet's hardest puzzle?

Who is behind Cicada 3301?

Nobody knows. Between January 2012 and 2014, someone using the name "3301" ran three rounds of cryptographic puzzles that opened with the same challenge: "Hello. We are looking for highly intelligent individuals," CBS News reported. The people running the project never gave an interview, never appeared on camera, and never confirmed it under a real name, in the original rounds or in the messages that followed them. Journalists and cryptographers who studied the puzzles have proposed several theories about who was behind them, covered below, but none has produced a confirmed name.

Where the first puzzle started

The first round began in January 2012, when an image reading "Hello. We are looking for highly intelligent individuals" appeared on 4chan, CBS News reported. Solvers who worked through it found cryptography, number theory, phone clues and QR codes; a separate account of that round, published by Rolling Stone, traces the chain through steganography, a book cipher and a reference to Mayan numerals before that year's trail went cold.

The 2013 round raised the stakes

A second round opened on January 4, 2013, CBS News reported, built around prime-number sequences and hidden audio files behind a new Twitter account; solvers who progressed far enough received an emailed test of philosophical, multiple-choice questions. Rolling Stone's account adds that this round also leaned on the occult writings of Aleister Crowley and on spectral analysis of sound files. As The Conversation described the same round, successful solvers were then contacted by email, "and then... we just don't know."

The 2014 round and the Liber Primus

The third round opened around January 4, 2014, when a Twitter post reading "Hello. Epiphany is upon you" sent solvers back into steganography and on to a hidden Tor address, The Register reported; the puzzle demanded, in the paper's words, knowledge of "cryptography, steganography, programming, computer networks, obscure literature and runes, and mathematics." That round produced a lengthy manuscript in an invented runic alphabet, titled Liber Primus, Latin for "First Book." The book resurfaced in a later message, from January 2016, that told solvers "Liber Primus is the way," according to a Cybereason account of the puzzle's history.

How far the puzzle reached

The clues were not confined to screens. CBS News reported that organizers, or people acting on their behalf, left posters bearing the cicada image in cities including Paris, Warsaw, Seoul and Miami, so that solving the puzzle required someone in each city to physically find and photograph a sign. The scale of that coordination, repeated across three separate years, is one reason cryptographers took the project seriously rather than dismissing it as a single prankster's stunt.

The government and corporate theories

Alan Woodward, a computer security professor at the University of Surrey, first suspected the NSA or Britain's GCHQ, Rolling Stone reported, since both agencies have used public puzzles to find talent before. He later leaned toward a large corporation instead, telling Rolling Stone the puzzle's scale looked more like a company hunting for cryptographers than a spy agency's usual approach. The CIA's own head of recruitment told Rolling Stone the agency did not create it. Separately, cryptography professor Kenny Paterson told The Register the puzzles were "too well organised to be a practical joke," comparing them to Google's past recruitment billboards.

The art-project and privacy-group theories

Other observers doubt any institution is behind it at all. Game designer and cipher expert Elonka Dunin told Rolling Stone the project "just may be one group of people in a chat room giggling," more hobby than recruitment. A solver using the name Tekk told CBS News he believed the organizers wanted to release free, open cryptography and anonymity software to the public. Cicada's own messages describe an "international group" built around "liberty, privacy, security," with no name, symbol or membership roster, according to Rolling Stone's reporting.

A cypherpunk connection

A Cybereason account of the puzzle's history ties Cicada 3301 to the Cypherpunk movement of the early 1990s, noting that both used PGP encryption and Tor, both used language about liberty and privacy, and that a mailing-list address tied to the puzzle traced back to a cicada.berkeley.edu address associated with that movement. The same account describes the puzzles' stated purpose as recruiting help for "CAKES," a Cicada Anonymous Key Escrow System meant to protect whistleblowers, though it stops short of naming any individual.

What still has no answer

No footage or photograph of the organizers has ever surfaced. "No one knows who is behind the spooky tests, or if they do, they're not telling," The Register wrote in 2014, and that line still holds. Real or Legend files Cicada 3301 as unsolved: the puzzles, the posters and the later messages are real and well documented, but the authorship that solvers, journalists and cryptographers have chased since 2012 has never been confirmed by any person or agency named as a suspect.

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