The week of May 22, 2016

The strange and twisting case of r/A858, Reddit’s indecipherable Stonehenge

By Robert Guthrie

A little more than five years ago, a previously unused Reddit account began posting seemingly random strings of numbers and text in a new subreddit it had created. To the casual eye, there wasn’t much to see. The subreddit shared the same inscrutable set of numbers and letters as its moderator; the sidebar and comments provided no clarifying information.

If it was a mystery, it appeared a banal one. Like any number of niche subreddits, it seemed to serve some unknown, private purpose. Whoever was using it had no interest in drawing attention, and so it remained ignored and forgotten, letters and numbers quietly churning away in a overlooked corner of the web.

It’s not clear how the larger Reddit community discovered r/A858DE45F56D9BC9—whether by chance or through subtle hints—but soon enough, redditors saw those strings of letters and numbers and decided they looked like a code. And if it was a code, the online sleuths would set out to crack it.

Cryptic puzzles and group efforts to solve them are as old as the Internet itself; Usenet was plagued for a brief time in the ’90s by a series of nonsensical, possibly ciphered posts that came to be known as the Markovian Parallax Denigrate, and alternate reality games such as The Beast and I Love Bees have challenged online players to work together to solve their mysteries. And now, it’s never been easier to identify these mysteries and collaborate on them.

In the case of r/A858DE45F56D9BC9, it languished in obscurity for the better part of a year, until an AMA request asked for more information. “My big question is what do these seemingly random strings of numbers mean, do they correlate to something; is there some big joke I’m missing out on?” the post read. Though the mysterious moderator never responded, the request stoked interest, and a sister subreddit formed shortly afterward: r/Solving_A858.

Almost immediately a dedicated group of computer science students, amateur cryptographers, and motivated enthusiasts began trying to crack the code. The initial community was small and close-knit; the creator kept the subreddit private, only allowing those who showed promise to join. But that exclusivity didn’t last long, and the community soon opened to the public.

As tantalizingly obscure as the apparent code was the purpose of the postings. What could they be? Speculation was so rampant that a new subreddit sprang up just for sharing hypotheses: Maybe it was a numbers station using a one-time pad for decryption. It’s a team of programmers trying to find hidden talent, like with the Cicada 3301 challenge. It’s a control for a botnet. Other theories were more outlandish. Aliens. An AI. An insidious government program.

The most dedicated users often had the most sophisticated theories: “For quite some time I’ve believed A858 to be a piece of art that uses the “digital world” as its canvas,” speculated one moderator. “Hard to answer,” said another. “It’s an experiment. There are several components (to put it at its crudest): the mathematical/decrypting part and a social factor. I still am sure that the A858 is not only looking for very intelligent people, but is also studying behaviour.” One thing everyone seemed to agree on: there was a purpose behind the posts.

“We cannot disclose the purpose. A858 will end when the purpose is disclosed or discovered.”

At first there was more speculation than progress, but the group began to find illuminating patterns and inconsistencies. Fairly quickly, it became obvious that the titles of the posts were time stamps. Easter eggs or messages were hidden in some: a series from December 2011 that wasn’t decoded until much later contained messages reading “Happy New Year 2001” [sic] and “NO 2 SOPA,” a reference to the Stop Online Piracy Act.

Most of the messages were not just encoded, but encrypted—the difference between the two being that encoded information is meant to be read in a different format, like ASCII, and can be unraveled with the right algorithm, but encrypted data is meant to remain secret. But more solvable messages began to appear—even though the simplest were fairly complex for a layperson to crack. The creator of r/A858 was aware of the growing attention and also began dropping hints, jokes, or words of encouragement. One post featured an ASCII-art image of Stonehenge, referencing a comment that had called the the puzzle the “Stonehenge of Reddit.” Another series revealed .gif images of Sarah Palin, captioned “MAVRICK.”

On more than a few occasions, the puzzle master acknowledged its following. Very early on, a user bought gold for the mysterious redditor. In response came an MD5-hashed message reading simply “Gold” and “ThankYou.” Personal messages to the mods of r/Solving_A858 chastised them about “weak puzzle” and exhorted them to “try more.” Even these “easy” posts required considerable work to decipher.

Whoever u/A858 was, there seemed to be limits to the amount of attention he or she (or they) wanted. When the puzzles appeared on lists of “Weird Internet Mysteries” or mainstream Reddit threads—as they inevitably did—the subreddit would suddenly go private, locking out the newly curious. Often all the previous posts would be deleted, which had been happening anyway, but often corresponded to a new spike in interest. Whoever was behind the puzzle seemed to enjoy a little attention, but not too much.

Until recently, r/A858 and r/Solving_A858 enjoyed a convivial, if one-sided relationship—the enigma would post ciphers and the enthusiasts would try to solve them, to occasional encouragement from the creator. Still, after four years, most of the posts remained encrypted, defying all attempts from all comers.

That all changed in August 2015. An account appeared in the r/Solving_A858 subreddit and began posting hexadecimal chains that matched those in r/A858. It wasn’t long before forum-goers recognized that the mysterious creator was doing an AMA. Moderators broke the code and created a script that automated the encoding and decoding process, allowing users to quickly ask questions. The mysterious minds behind r/A858, after years of silence, were suddenly talkative, though their answers tended to be as cryptic as their code.

The new account claimed the puzzles were created by a group, as part of their paid work, though they refused to elaborate. Asked why, after all this time, they would break their silence, the response was simply: “The audience was getting frustrated.” As to its purpose, “We cannot disclose the purpose. A858 will end when the purpose is disclosed or discovered.”

Surprisingly, the puzzle-makers revealed that “One post has been decrypted. Nobody noticed but us.” A woman in the U.K. had apparently succeeded where so many had failed, only to later delete her account; the creators would say no more.

The AMA ended the encoded text being converted to all zeroes. It left the amateur code-breakers with perhaps more questions than answers, but also with a renewed enthusiasm.

The mysterious minds behind r/A858, after years of silence, were suddenly talkative, though their answers tended to be just as cryptic as their code.

It also brought some new minds and fresh eyes to the project, and before long new posts were being decoded. A relative newcomer discovered how to decrypt the “Happy New Year” and “NO 2 SOPA” posts, which had until then gone undiscovered. This led to a huge discovery: a decryption key that many of the early posts in r/A858 shared. Users worked diligently to uncover the meanings of these posts, only to find that they were further obscured—the posts decrypted to globally unique identifiers (a singular 128-bit value used to identify certain computing resources) which got the team closer, but revealed nothing conclusive. In addition to ASCII art, some of the posts appeared to be coordinates in North Korea, fueling speculation that r/A858 was somehow related to counterintelligence.

It seemed that, after all those years of frustration, the dedicated felt a solution might be at hand. Interest and participation was at an all-time high. More posts were being decoded or decrypted than ever before.

Then, without warning, r/A858 went private.

It wasn’t the first time this had happened, and the longtimers knew not to panic. All the posts had been archived and the solutions added to the wiki; most assumed the subreddit would open again once interest had died down, or some other unknown criteria had been fulfilled.

And after a while, it did. Except this time there were no new posts, only a short sidebar message: “The A858 Project Has Concluded. You may unsubscribe.”

The timing of the update, March 29, 2016, led some to hope it might be an April Fool’s prank—the puzzle-makers weren’t above having a little fun with their followers. But when the subreddit went private again and stayed private, people started to worry. When u/A858 deleted their account, followers were even more alarmed.

Some of the r/Solving_A858 moderators tried to take matters into their own hands. “Within an hour of the subreddit shutting down and A858 deleting his account I submitted a request to takeover the subreddit,” said one moderator, eathed. “A few weeks later I was told that I can not have control due to someone else already being a moderator. This means that A858 appointed someone before deleting his account. I hope this means that there is more in store for us later down the line.”

No one knows who was given control of r/A858, but it has kept hope alive. In fact, the faithful of r/Solving_A858 are almost universally convinced that the project, whatever that may be, is not in fact finished. “A858 may have deleted his main accounts, but we found out that the subreddit is still in his control from the redditrequests. Therefore, I don’t think A858 is truly over,” said jdaher, who’d first discovered the “Happy New Year 2001” message. “I have a feeling someone will try to come forward as the person behind A858 or someone claiming to have solved the mystery.” He warned that if so, it wouldn’t be the first time a troll or hoaxer without proof claimed to have solved A858. User augenwiehimmel succinctly summarized a perhaps collective mood of resolve: “No. It’s not over. I’m hopping mad, but there’s a reason for A858 to act like this.”

It has now been more than a month since r/A858 went private, and no new messages have been decrypted. But there’s plenty of work left to be done. All the previous hexadecimal strings have been archived, and all of the solutions are available on the wiki. Perhaps the project truly is over, but the AMA stated quite clearly: “When the purpose is discovered or disclosed it will be obvious to all.” Today, that is most definitely not the case. Those dedicated to unraveling the mystery are discouraged, but they aren’t giving up—not until they have answers. “I only hope A858 actually has a purpose,” said jdaher. “I don’t particularly care if it is a good one.”

Illustration by J Longo