Previous Challenges
Previous Challenges
Thank you for lending us your sleuthing services at this most momentous moment! With the national election just over six months away we have very little time to rectify a repugnant wrong. At this stage in our investigations, it is pretty clear that a small company in the Midwest is much more than it appears to be. We believe that Hancock’s Garden Supply Company is actually involved in a variety of illegal activities, running the gambit of drug smuggling to the illicit importing of rare rainforest flora. The stink emanating from their business is something more than just fertilizer!
We believe that HGS Co is using the profits of their questionable activities to fund domestic terrorist organizations intent on causing mayhem to explicitly disrupt the upcoming election. We are lacking just three pieces of crucial information before we can prosecute these shady gardeners:
1. The name and location of the offshore bank HGS Co is using to launder their money.
2. The bank account number, probably a 7-10 digit number.
3. The combination to a wall safe thought to be holding the evidence that should plant them behind bars once and for all.
Before enlisting your help, we had a brave agent deep undercover working at HGS Co. Before being exfiltrated, she uncovered an enormous amount of dirt about the inner workings of this corrupt group of gardeners. While much of their important information was often encrypted, our agent discovered that HGS Co primarily used three different ciphers, codenamed FLOWER, VEGETABLE, and FRUIT.
FLOWER: It appears that this cipher uses a standard Vigenère Square in a unique way. The plaintext is organized into pairs of letters and each letter of the keyword is written below each pair of letters of the plaintext, repeated as necessary. To encrypt a pair of letters, find the first letter on the top row of the Vigenère Square and the second letter in the row designated by the keyword letter. Think of those two letters forming two corners of a rectangle (unless these two letters are in the same column). The ciphertext letters then become the two other corners of the rectangle, writing the upper letter first (if the two letters are in the same column, the ciphertext letters are those that are immediately to the right). See the following example:
Plaintext: this is my secret message
Key: kryptos
PT: th is is my se cr et me ss ag ex
Key: k r y p t o s k r y p
CT: XD BZ UG JB LL DQ BW UW BJ IY IT
FRUIT: This cipher uses three keywords. Starting with a 5 X 5 grid, the first keyword is written in row by row omitting any repeated letters. The remaining letters of the alphabet (excluding J) are written in alphabetical order in the remaining cells. The second keyword (of five distinct letters) is used to label the columns and the third keyword (also five distinct letters) is used to label the rows. Every letter of the plaintext can now be replaced by the pair of letters that represent the row and column headings for that letter in the grid.
VEGETABLE: This is a transposition cipher in which the plaintext is first written in a square grid, row by row. The ciphertext is read from the grid according to some predetermined pattern. For example, one might start in the upper left and read the ciphertext down the first column, up the second column, down the third column, etc. Alternatively, the pattern might be a spiral starting in any corner (or in the middle). The pattern could be anything!
Just before barely escaping with her life, our august agent obtained the following encrypted clues that we believe represent the missing information we so desperately need to put these conscience-soiled landscapers behind bars. While we believe we know what each encrypted clue represents, we do not know which of the three ciphers was used to encipher it! Now you are beginning to see why we called you!
Please help us decrypt the following messages:
Challenge 1: Determine the name and location of the bank being used to launder the money. We expect this bank may be located in Belize, Singapore, Hong Kong, or the Cayman Islands. All we have is the following bit of ciphertext that was scrawled on a scrap of paper:
EEOEL AEAOA LRORE PMRLA OPMGE PLENG EPORO AEPLR ERMGM RLAEP OAEPE GLRLA MAMRL ALPER LEORM ELEOR LROPM RLELA MPLEE RLROP EPEAM RLAOA MRLAL PLRME LEORE P
[Solution]
Challenge 2: Uncover the bank account number being used. Our agent found this account number in a spreadsheet on the culprit’s computer, but it was encrypted:
ESMN AGNL NVIS VPUB JIWZ FECG LKCM CYIE PYGM
[Solution]
Challenge 3: We need the combination of the safe that holds the rest of the incriminating documents. This ciphertext was found on a piece of paper taped to the back of a painting that was hanging in front of the wall safe. It must be the combination!
EFNT EASP HOIF GOEH TIDR RDIE NEFT SEYA NHNE EATI TTLR HNNT TNFE YGTH EEVL TNES
[Solution]
Challenge 1
URGENT! URGENT! URGENT! URGENT! URGENT! URGENT!
The presence of three moles (double agents) in our organization has caused us to shut down our codebreaking section immediately. You are the only one we can definitely trust to help us uncover these undercover double-crossers! We’ve recently noticed some strange postcards being sent to an anonymous PO Box, that we believe contain the names of the traitorous members of our select group of cryptanalysts. We are certain they are members of our Black Chamber operations unit (roster attached). If you can unmask these masqueraders, please send along their names as soon as you can!
[Solution]
Challenge 2
Billy "Moneybags" Jones is a high-level gangster who is in jail awaiting trial for money laundering. He is not allowed visitors, but his girlfriend Brenda writes to him regularly. It is believed Billy is planning a jailbreak and Brenda is going to meet up with him afterward to flee the country. Of course, their communications are read by the authorities so they must write in code. Brenda not-so-cleverly sent their coded message as a "registration number" in a letter hoping to avoid detection.
A former associate, Eddy, agreed to testify against Billy and joined the witness protection program. Eddy was reviewing Brenda's letter and believed he had cracked the code when he was killed while out on his morning run (presumably to prevent him from testifying).
Eddy believed that the pair were communicating using a modified version of the Playfair cipher. He was just beginning to figure out the new rules when he was killed. His notes indicate that the rules were explained by referring to classified ads in a newspaper that was available to inmates called the Pennywise Classifieds. Eddy seems to have figured out the rules for encoding if the pair of letters form a rectangle but hadn't finished figuring out the remaining two rules for encrypting letters in the same row or column. Eddy also believed that Billy and Brenda are likely to rendezvous in Tucson, Arizona so it is likely those words appear in the decoded message.
Please help complete Eddy's job to decipher the message and let us know where Brenda and Billy plan to meet.
[Solution]
Challenge 3
Okay, this assignment is coming from the “big man” himself! The Department of Justice is hot on the trail of an organized crime ring. Because of a confidential informant at Western Union, the DOJ as been able to intercept many telegrams between members of this group of criminals. Often, these telegrams are encrypted using the Vigenère cipher with a repeated keyword, which the government cryptanalysts have been able to break. But, they have apparently decided to change their encryption method – right before a big meeting is supposed to take place! A wire-tap recorded the phone conversation between two members of this mob of smugglers that seems to reveal the new method of encryption. Yet, the DOJ does not know how to go about breaking it. They’re pretty sure the meeting will take place next Tuesday, but they don’t know when or where. A recently intercepted telegram probably gives the details, but it is, of course, encrypted! Please help and decrypt the telegram for us!
[Solution]
Challenge 1
[Solution]
Challenge 2
We thought that bootlegging went out with Prohibition in 1933, but it appears to still (no pun intended) be going strong! For example, rare, small-batch bourbon companies are seeing their empty bottles being sold for high prices on sites such as Ebay. Unscrupulous scoundrels buy the empty bottles, fill them with inferior whiskey, and sell them to unsuspecting booze aficionados for exorbitant prices. Our small strike team has been charged with breaking up one of the larger of these sauce swindling syndicates. The first phase of our operation was quite successful, as one of our agents actually learned the encryption system being used by these moonshine manipulators to coordinate their illegal sales.
Unfortunately, they seem to be changing their keyword about once a week and we are unable to figure out what it is. We've intercepted the following message that we believe will indicate a time and place where a big shipment will be coming though. If we can get there first, we can set up an ambush and put these whiskey wranglers out of business!
[Solution]
Challenge 3
Mrs. Krabappel is a math teacher at Springfield Middle School. On Thursday, she planned to give tests to both her 4th and 5th period classes, but a fire drill at the beginning of 5th period prevented that class from getting the test. Since it was a holiday weekend the test will now be delayed for the 5th period class until Tuesday.
Mrs. Krabappel found a paper in the desk of one of her 4th period students that she believes was left intentionally for the student who sits at the same desk during 5th period. She knows the students are friends and suspects the 4th period student was leaving the paper to somehow help the 5th period student on the test. However, the paper just looks like a puzzle worksheet with some gibberish written at the bottom. She's asked for our help to decipher the gibberish before her class meets on Tuesday. Please help Mrs. Krabappel determine if her students were trying to put one over on her or if the student is just a fan of crosswords.
[Solution]
Challenge 1
What started out as a series of pranks has now gotten a little more serious. Two zoom bombers, going by the aliases Caesar and Salad, are starting to wreck some serious havoc. They have been disrupting a series of important meetings of the National Cryptographic Association. We have one suspect in custody (Caesar, whose real name is Julie DeGaulle), but we don’t have enough evidence to hold her for long. She was not in possession of her computer when we arrested her and we expect that her computer has all of the zoom bombing code needed to both convict her and stop any future attacks from Salad. DeGaulle has been held at a Juvenile facility for several days and she has been sending daily letters to her brother, who we think might be passing them along to Salad. Could DeGaulle be giving Salad secret instructions in these innocent looking letters? If you can detect any secret messages in these letters, please let us know as soon as possible! We’ve scanned the five letters in a single document for you to examine.
[Solution]
Challenge 2
Kryptos agents, we are in desperate need of your help! A large supply of Covid-19 vaccines have been taken hostage by the amoral gang known as ®an$omWar€4U$. They have taken control of an electronic lock on a large freezer which is storing thousands of these precious vaccines. Even worse, every hour that the $4 million dollar ransom is not paid, they will increase the temperature of the freezer. We have intercepted an encrypted message between the leader of ® an$omWare4U$ and one of the gang members who is their techie. Most likely this message indicates how the freezer can be unlocked. An unencrypted phone call between these two made it clear that the method of encryption is the Vigenere cipher using a running key. They said that the key would be the start of their favorite “literary work”. Of course, we have no idea what book this might be, so reading this encrypted message seems close to impossible. Can you please help us read the message and unlock the freezer before thousands of doses of the vaccine are ruined?
BAAFJ EHZVB SURME RLZJB KQDAX UXYEX NXWHZ ZQBGK VBGXV XLHMK XZXFQ PIFMT BUCWA XWZSS TPPDS SQOAE AIOXV RISBQ SRWFO MFMGF DTVFO ARH
[Solution]
Challenge 3
A rival group to the gang ®an$omWar€4U$ called the Malware Extortionists (Or MEs) has been discovered to have plans to outsmart the ®an$omWar€4U$ criminals and steal both the vaccine and ransom money for themselves. One of our excellent investigators has intercepted two communications between members of the group. That same investigator managed to zoom bomb a meeting of the MEs long enough to grab a screen shot at an opportune time when we believe they were discussing their method of encryption. We hope that some clues can be found in the screenshot that will help decode the message. Please help!
First intercepted message:
tbnvu oniso aeard evmwu dnrae eoooa eddlt tmrna evbhf astdd cokuy eieoc olrrc 4ciey eesol nirld andii soiet rehme cuera kmcnw wre
Second intercepted message:
uooih keinb turam rnstt nulac afemn rftrr rnpif psuwe dhera ftsuo nhhcc hsola stnei sbget ooate aataf etsdc oattn eidle teyge nie
[Solution]
Challenge 1
A group seems intent on hacking into a government website used to collect U.S. Census data. It is unclear whether they intend to steal data or just disrupt the entire process. We have been monitoring an SMS-based conversation between two of the members (who also happen to be members of the Fellowship of Armchair Cryptologists), but they recently started using some sort of cipher. We intercepted two recent text exchanges between these two individuals. The first set of texts are in the clear, but the second set is encrypted. We hope you can figure out what information the encrypted portion of these texts contain. Please sent your cryptanalysis results as soon as possible!
[Solution]
Challenge 2
The Las Vegas Scandal Detection Squad (LVSDS) is investigating a pair of men they believe to be cheating on the blackjack tables. They also believe one of the dealers is involved in the scandal. An undercover LVSDS agent was able to recover a polaroid picture with some numbers on the back that one of the suspects discarded in the trash. They believe this is some sort of secret message. Can you help them decipher it before the big (virtual, of course) blackjack tournament on April 21st?
[Solution]
Challenge 3
Unfortunately, the threat of biological warfare continues to grow. This time, the threat is coming from a very small, yet very well-funded, extremist group. We have evidence that this group has developed a fast-spreading virus and is in the process of transporting a small sample to a location that will allow them to release it at any time. If we can determine where they plan on bringing the virus sample, we can arrange for a team of Special Forces to intercept the virus and, hopefully, as many of the terrorists as possible. We know that the virus sample is sensitive to temperature and needs to be kept cool, right at 42 degrees F, in order to keep it stable and alive. Thus, we expect that it will be transported by hand, rather than through any sort of public shipping company.
One of these bio-terrorists inadvertently used an unencrypted text app to send a recent message. The message itself, however, was clearly encrypted before being sent via this app. While we haven’t been able to crack their cipher, we did manage to trace the origin of the text message and we sent in a pair of agents to secretly enter the small apartment. The apartment was mostly empty, but the agents did find a mysterious sheet of jumbled letters taped to the underside of a desk drawer. They sent the sheet of paper directly to our lab for analysis. Since they also found a candle nearby, our lab technicians suggested we look for anything written in invisible ink. Bingo! When heated, some odd arcs started to appear. Even more surprising, this invisible ink appeared to be in different colors. The lab enhanced the colors and created this composite for you to study.
So, the only clues we have are a sheet of paper with colored curves and the apparently nonsensical text message. Can you help us discover where this virus is being sent?
Text message:
EEETE TESOE HOIXL OUEPR MGEFE GIAGW ONEOO AGOIS AIATD ELRND EYWWE VNLNP LRORR VEEAR ESTDR DFNEK ERATY ERTBE HSHOB EVAPF RDWOD GAIUS TLYLN II
[Solution]
Challenge 1
KRYPTOS has just been contacted by Special Agent Torey from the Department of Justice to help them with a case! Please see the letter from the DOJ to read all about it. The D.O.J. also sent along a Suspect Dossier and a list of encrypted PINs.
As the letter says, we need to figure out the username and password for the website: dirtydeeds4u.com. Please send these along as soon as you have them and we'll make sure the D.O.J gets them.
[Solution]
Challenge 2
A ring of jewel thieves has been at work in the area. They have recently gained access to an explosive device that would help them break into a high level target. Our undercover agent had a major breakthrough when she found what she believes to be the explanation for enciphering the messages used for communication among the ring leaders. Unfortunately we think the thieves suspect that their communications are compromised and will change their encryption method. We have what we believe might be the last message that was encrypted using the known scheme. Please help us decipher the message to see if we can stop the group in time.
Explanation of encryption method
Ciphertext message:
tbcIm dwaoo sgeee dtssI banoo ccrru rrrau apnhe
ahesn mmeva cmndo cuntg cIsmh btIeg lIIkr evafd
detet enonO caoee nntds
[Solution]
Challenge 3
We can’t believe our luck! Our undercover agent walked in while the ring leader was encrypting a message using the new scheme. She managed to take a picture of a scrap of paper on the desk that must indicate how messages are encrypted, although she noticed quite a few other scraps of paper with similar squares of letters in various arrangements. Shortly afterwards we intercepted a message that was probably encrypted using this method. However, neither we, nor the agent, are quite sure how this scheme works. We hope you can help us figure it out and break the encrypted message. We are worried our agent has been discovered so she is going to lay low. Please send us the contents of the encrypted message as soon as possible!
Scrap of paper: (file)
Intercepted message:
VXX CAV TQE GFZ EhV AIX REF NLE FFK QUA ONZ KLN LEW ATZ
KMH HKF EIX GBP RHO LHD XZZ KGT AIX RHL LHO NLN GCX ZWP
BCX HLE SRB LSH REI LHT MHV UPW ATZ BCX
[Solution]
Challenge 1
We have one chance to grab a known cryptocurrency counterfeiter. For some reason, this heinous hacker has reverted to a very low tech form of communication to set up a meeting where we expect her to exchange a new chip capable of dominating the mining operations of ByteCoin. Our trench-coated techies have noticed a series of personal ads places over the last month in a national newspaper. We have clipped the ads (and circled the ones we are sure came from the counterfeiter) and placed them all in one file to send to you in the hopes that you can help us decipher their meaning. As usual, time is of the essence. No more ads have appeared, so we believe the high stakes rendezvous will take place soon. Please help us figure out what these perplexing personals mean!
[Solution]
Challenge 2
Follow this link to receive a special invitation! [link to invitation]
[Solution]
Challenge 3
Dear Crypto Consultants:
We are trying to break up an international internet Trolling operation that has the potential to cause harm to civilians. The group, led by an individual who goes by the name of “Grendel”, has moved well beyond influencing social media sites. Grendel is now using a few well-placed individuals to infiltrate into some local grass roots organizations in order to convince them to participate in some demonstrations and/or protest marches. Grendel has infiltrated organizations from different sides of the political spectrum and plans to have each of them protesting on the streets on the same day. We fear that the results could turn disastrous and, possibly, violent. Up until now, we have been able to intercept their communications via some computer and phone surveillance systems we have in place. However, as we get closer to the day of the Big Event (this is how Grendel refers to the operation), they have started encrypting their messages. Grendel has sent one encrypted message to his group of trolls several days ago, but now there has been no chatter on any of the usual communication links. We feel they have gone “silent” and that the Big Event must be close at hand. But, we have no idea when or where this event is planned to take place. This is where we need your help!
A copy of the last encrypted message from Grendel is given below. While we do not know who Grendel is, we have identified one of his trolls. An on-site security team managed to find a crumpled up, coffee-stained, piece of paper that might just hold the key to their encryption scheme. I hope you can make some sense out of it. If you manage to decrypt this, please let us know as soon as possible!
Sincerely,
G. W. Oman.
Hdqtrs.
CT:
WPIQT BAVNV UKQZP NFPDW VCZMX XWWWU MCEHA VZVSN WNWOE FBEFF OWSWE OFHWG FHQAX LDEIA BKWTX KZPII OLLHJ GLQBY AEKVQ SEBGN VUEMQ NHADS HEXKL AAHOW NBOWP QGOID XAQUH NFKSR PAATX FUCTT FOLNW ZVOWV NUKVQ SEBGB VTAWQ CLCKN SQXYC KNPAN KWWEM QIOAT EUFPB LTEHF TELOW KUQHU OHYVF JPHNA QQBPT XSVCV MJLEB QUDUN AQCTC KNKUQ HUOXF NWOVQ KSRWO TFBRI FIIQK QZNUK JWLMF HWGKF OPSYO RVVPA ANRVE JUWTP WAVVM BNWAX OUOMH SUHWW AEFLI QJLES PVLAE KFJLI ZEHBC SN
[link to a text file with the CT]
[Solution]
Challenge 1
I am so glad that you have agreed to act as a consultant for us. As I explained to you earlier, we are very close to catching up with the so called “Red River Gang” who have been dealing in illegal arms shipments. We feel that we are getting very close to apprehending the entire gang.
We recently identified one of these individuals and managed to gain entrance to his apartment. It was mostly cleared out, however we found a very odd Tax Form in a drawer with a wooden cipher machine. The cipher machine has a stationary outer ring showing all 26 letters of the alphabet. There are also four “inner” rings which rotate freely. The numerals 1-100 seem to be represented on these movable disks. I’ll send you a copy of the Tax Form and a picture of the cipher machine we found in the hopes that you can make some sense of it all. We’re pretty sure that there is an upcoming meeting or arms delivery, and we hope that we can catch the entire gang at that time. Please help us out as quickly as you can!
[Solution]
Challenge 2
The Red River Gang continues to elude us but our inside source reveals that the leaders are fighting amongst themselves causing tension in the group. We believe that members are taking sides and Jackson is out. Our source managed to copy down an encrypted message before it was sent. She knows that the gang has been communicating using the Phillips cipher but she does not know the code word. However, she believes that Jackson is referred to by name in the message. Please help us decipher the code and catch the gang. Our source may be in danger!
Our informant tells us this is likely enciphered using the Phillips cipher with shifted rows and a left to right fill. See here for details: Phillips cipher
CT: SMMFPOW XRLSM HVEML YA ARL LEPZH QV BDM POZVZS PLGQUVO
[Solution]
Challenge 3
Our contact with the Red River Gang is under suspicion. She managed to get us a very valuable message that she thinks was encrypted using the Vigenere cipher. However, she was questioned before she could send us the key. She later posted a webpage which we think is her way of communicating the key for the Vigenère cipher, but we can’t figure it out. Please help find the key and decode the message!
CT: pzzwd gdaei avpou dfvdv gaeci tiip
Website: [http://www.wou.edu/~beaverc/kryptos/2017/Challenge3.htm]
[Solution]
Challenge 1
As chief cryptanalyst for the United States Coast Guard, your primary responsibility is cryptanalyzing intercepted traffic from individuals bringing bootleg liquor into the United States. Working for large organized crime syndicates based in New York and Chicago, ship captains make use of Western Union telegrams to take illegal liquor orders and determine rendezvous points for delivery. These ships often sail from Belize or Honduras, occasionally stopping in Cuba, enter the Gulf of Mexico and stealthily make their way towards New Orleans. Once they are close to shore, the bootleggers, or rumrunners, rendezvous with smaller boats to unload the crates of whisky, gin, and other contraband.
We have just received the following telegram which we hope will lead us to a location and time where a rumrunner is offloading their supplies. Most likely this will happen in the next few days, so speed is of the essence! Can you help us decipher this message?
[Solution]
Challenge 2
Our offices are trying to execute a search warrant on a suspect’s uPhone, however we cannot get past the password screen. We do know that the owner of the phone has used fairly simple one word passwords in the past, but since the uPhone is programmed to automatically destroy all data after three incorrect login attempts, we really need to get this right the first time. Or, should I say, the third time. Our local “techies” have already entered two incorrect passwords based on some poor reasoning on their part. So, we have one attempt left.
When the uPhone is initially powered on it shows a sequence of images of clocks. We’ve captured these images in the accompanying file (read left to right, top to bottom). This is the only clue we have to go on. Can you make any sense of these bizarre images and give us the password to unlock the phone?
[Solution]
Challenge 3
Howard Bannister was suspected of being part of a ring of thieves stealing precious rocks and minerals from a mining company in the Midwest and passing them to a contact in San Francisco, CA. His elaborate scheme involved trucking companies that would pick up his cargo and pass it off to other truckers on various routes. The police tracked Howard to the Hotel Bristol in San Francisco where they believed he was going to meet his contact. The police barged into his hotel room and found him at his desk writing a letter. Upon realizing he was caught, Howard ingested a poisonous capsule and died before he could be questioned. Police confiscated all items on the desk including a rotary phone, a set of keys, a pencil and some paper with numbers on it. The paper appears to be some code and police are hopeful it gives information either about the contact or the secret route used when shipping the stolen rocks. Please help us decipher the code found with Mr. Bannister.
[Solution]
Challenge 1
Thank you for agreeing to help us. As you probably know, an international gang of art thieves has struck again! This time successfully stealing a priceless masterpiece from the Uffizi Gallery! Unbelievable! We know the thieves have plans to meet up sometime soon in order to negotiate a quick sale with an unknown buyer. In an earlier attempt to infiltrate this wily gang we managed to obtain a smartphone belonging to one of the gang members. We hope that the phone will have some information on it that will help lead us to the upcoming meeting. However, the phone is password protected and we are pretty sure that ANY attempt to enter the wrong password will completely erase all of its content. All we have access to is the image on the Lock Screen [see attached image below]. Is there any way that this image contains the password? In the past we know that the owner of the phone has used simple one word passwords typically associated with nature or science. Past passwords have been “geology”, “evolution”, and “proton”. If you can use the image to uncover the password our coalition will be eternally grateful!
[Solution]
Challenge 2
Our assumption was correct - the image did contain a password! Unfortunately, there was only a single document on the phone: a picture of a handwritten document [see attached file below]. As you can see, it is clearly encrypted! The international coalition formed to help bring down this gang of thieves was quite disappointed in this development. We are still hoping that this document will lead us to the thieves and the buyer while they are still in possession of the stolen art. We are asking for your help once again. Can you decrypt the message for us? Clearly time is of the essence, so please let us know the moment you have readable plaintext for us.
[Solution]
Challenge 3
This is becoming much more complicated than we originally thought! Thanks to your earlier work, we have yet another clue: a text message that was probably encrypted using the popular Ragbaby cipher. We are pretty sure that the first word is “meet” and will finally give us the meeting time and place where we can apprehend the art thieves.
Our international coalition to catch these thieves is weakening. We desperately need to know when and where to find this gang! We feel we will have only one chance to apprehend the thieves before the coalition crumbles completely. Can you decrypt this text so we can finally put these ruthless criminals behind bars!
Text Message:
NACZ AOGIOUK CNMPB ZOGONMM CVH VSZK HTSUC NMHIZYZHQF MDMEGQ MMOBNL RZBET QYV FTET QLIQZ NTWO
[Solution]
Challenge 1
We found a scrap of paper tucked inside the wallet of Blaise Pascal (clearly an alias) who we feel is a junior member of a team planning an armored car robbery. We think that this note will give us the time and location of the planned heist, but the text is so short we have not been successful with the usual methods of frequency analysis. We weren't expecting a very complicated cipher, but maybe this gang is more sophisticated than we originally thought. We expect the robbery to occur within the next few days, so if you can give us any help ASAP that would be great.
[Solution]
Challenge 2
The National Spy Agency has been monitoring all communications of a terrorist group known as The Phantoms. Special Agent Guy Gadbois has acquired intelligence that an incident will take place at the Brighton Bridge but does not know much more. The terrorists realized they were being monitored and quickly sent the last known communication in code. It is believed it contains information about the attack (location, time, date, etc.) that will allow us to thwart their intentions. Please help us decrypt this so we know when this attack may occur!
Intercepted communication:
uzs yfr uvjf kay | b toh abkqhb khgb tv hbk lk t tv bg akwv obgr muc utb gkzt qn
This just in! (Hint given during the competition)
A recent SIGINT source indicates that "the cipher method used can be found by reading the first part of the ciphertext". We're not exactly sure what this means, but hopefully it will help provide you with a clue to breaking this confounding cipher.
[Solution]
Challenge 3
We have been following a suspect (Emily Brower) who we believe has recently stolen some important documents. Our surveillance team lost her briefly yesterday while she was in Central Park, but we are pretty sure she placed the documents in a dead drop that we think will be serviced by a foreign diplomat (Gunther Worsteadt) who is suspected of spying for a variety of governments. Because of his diplomatic credentials we cannot bring Worsteadt in for questioning, but through some clandestine means of questionable legality we were able to briefly examine the contents of his wallet. We found a scrap of paper that is clearly some coded message which we believe identifies the location of the dead drop. We took a photo of the paper before restoring it to its proper place in Worsteadt's wallet. We need you to help us decipher this message so we can catch him red-handed at the dead drop. With such incriminating evidence, his diplomatic immunity will not be able to offer him much protection.
While we do not know the nature of the enciphering scheme, an operative did manage a quick look into Brower's apartment while she was out. There was some work on her desk that could clearly be related to the method she used to encipher the message to Worsteadt. We'll pass along a photo of this paraphernalia to you as well.
Time is of the essence for this one! We hope to hear from you soon.
This Just In! (Hint given during the competition)
Cryptanalysts from a friendly country are pretty certain that the turning grille used for this encryption is not - repeat not - pictured in the photos we took. It looks like our work is cut out for us (sorry, no pun intended).
[Solution]
Challenge 1
[Solution]
Challenge 2
We intercepted the following unencrypted snippet before the transmission dissolved into a long string of numbers. We’re at a loss at how to proceed. Any help you can provide would be greatly appreciated.
sorry i missed your last Interchange. i will use our agreed upon [Additive] American Code to deliver the rest of the Information. Standard [Additive] keyword will be used. [CAPS ONLY]
148 154 155 172 145 152 152 157 154 159
174 160 148 145 159 167 172 169 163 148
154 155 172 145 152 152 169 154 173 173
149 157 148 157 150 174 169 161 151 145
149 154 174 163 154 140 148 156 150 157
159 148 154 155 172 145 152 152 146 167
163 168 147 153 140 149 158 174 159 153
142 146 145 151 166 155 143 144 135 145
168 159 148 154 155 172 145 152 152 167
157 159 172 145 152 140 145 161 166 174
148 138 134 145 152 165 175 156 135 137
148 154 155 172 145 152 152 145 169 174
162 145 136 137 158 169 172 155 152 159
147 159 171 155 166 145 153 156
[Solution]
Challenge 3
For this challenge you will be given the ciphertext after it has been encoded via the Modified Progressive Shift Cipher (MPSC). Here is how Alice enciphers a message to Bob in MPSC:
Step 1: Alice and Bob agree on a keyword, say “treenut”, and remove duplicate letters leaving them with the reduced keyword “trenu”.
Step 2: The Alphabet Line is created by writing the reduced keyword followed by the remaining English letters in alphabetical order:
t r e n u a b c d f g h i j k l m o p q s v w x y z
Step 3: The plaintext message is written down keeping the word lengths intact. Under the first letter of the first word, write a “1” and continue numbering the letters in the first word sequentially. Under the first letter of the second word, write a “2” and continue numbering the letters in the second word sequentially. This process continues in the obvious way (first letter of third word is given a “3” …). For example:
t h i s i s t h e o n l y e x a m p l e
1 2 3 4 2 3 3 4 5 4 5 6 7 5 6 7 8 9 10 11
Step 4: To encipher the first “t”, locate “t” in your alphabet line and shift 1 letter to the right (since there is a 1 under the “t”) to become a “R”. The letter “h” is shifted two letters to the right from its place in the alphabet line to become a “J”. “i” is shifted 3 letters to become “L”. This process continues: each letter is shifted to the right a distance of d where d is the numeral below the letter. If you reach the end of the alphabet line, just wrap around to the beginning. For this example we have:
Plain: t h i s i s t h e o n l y e x a m p l e
1 2 3 4 2 3 3 4 5 4 5 6 7 5 6 7 8 9 10 11
Cipher: R J L Y K X N L C V D V A C N I Y R Z J
Step 5: The ciphertext is now transmitted, keeping word lengths intact. Since Bob knows the keyword, he can easily re-create the alphabet line, write down the appropriate numerals under the ciphertext and start shifting to the left to decipher the message.
The following ciphertext was encoded using MPSC. Recover the plaintext.
RW PYXZ TFUAFOE TAHAGFRKW MHXX KWMHO HCMTGQO
[Solution]
Challenge 1
ALERT * ALERT * ALERT * ALERT * ALERT * ALERT * ALERT * ALERT * ALERT * ALERT * ALERT * ALERT
Command has two prisoners who are suspected of being SVR spies, but we haven’t been able to get any information out of them yet. Their cover stories seem to check out and we’ll have to let them go if no additional information is forthcoming. While the detainees are not able to speak, late last night a hidden microphone picked up some attempt at communication between the two. We managed to record the four short “bursts” that we assume is some sort of pre-arranged code. We have no information to go on at this point so we need to know if there was any useful information conveyed in this exchange. Please send us any useful information as soon as you have it.
ALERT * ALERT * ALERT * ALERT * ALERT * ALERT * ALERT * ALERT * ALERT * ALERT * ALERT * ALERT
Audio File 1: [mp3 format] [wma format]
Audio File 2: [mp3 format] [wma format]
Audio File 3: [mp3 format] [wma format]
Audio File 4: [mp3 format] [wma format]
[Solution]
Challenge 2
Two prisoners are being held at command, suspected of being SVR spies. When the prisoners were apprehended, a third person was seen running from the scene. As the person fled, a piece of paper fell from their pocket. The paper has nothing but garbled letters and we believe it to be an encrypted communication, but have no idea as to the method of encryption. Please help decode the message so we can pursue the third suspect and get evidence against the prisoners.
[Solution]
Challenge 3
We are pretty sure that Carolyn Gordon is using her position on a high ranking committee to profit from information she receives regarding various publicly traded stocks. While she herself is not overtly involved in any trading, we believe she is selling her information to several acquaintances that have made several recent trades which are highly suspicious. After obtaining a search warrant, thorough searches were conducted at Ms. Gordon’s residence as well as her suspected collaborators. One collaborator, a Mr. Raphael Cotrez, had some torn pieces of paper on a pile of rubbish next to his fireplace. Forensics determined that the pieces fit together into two strips. Yet, the letters on the assembled strips is meaningless to us:
Slip 1: YQDHvuhGTIokirdceiqlsZQCsfwPTWcytfupyja
Slip 2: lpnngafplvnnclnyhYOGgpcwefxzgjacouccdtbhTAZHi
While it was almost missed in the search, a portion of Ms. Gordon’s diary was also found. Some of the entries make it pretty clear that she was probably plotting some illegal behavior, but the evidence is pretty weak at this point. However, the strange text found in Mr. Cotrez’s apartment was also found in Ms. Gordon’s diary, albeit with a few extra spaces between the letters. This clearly links the two! We are now working under the assumption that the strange letters are some sort of code or cipher. All we need is to figure out how to decode these messages and hope that they clearly point to insider trading violations. Can you help us? A copy of Gordon’s diary is attached to this note. Time is of the essence as we do not have enough evidence to hold Gordon past the weekend, but we feel that if she thinks we’re close, she’ll flee the country
[Solution]
Challenge 1
I am writing to ask your help in a most delicate undertaking. While I am not at liberty to say how, I have recently come into the possession of a message which our Majesty deems critically important to matters involving the Crown. Unfortunately, the unscrupulous author of the text has apparently gone to great lengths to disguise its meaning, thereby committing an act of treason against King and Country. If the true meaning of these traitorous comments is revealed, the King’s men may be able to act swiftly to apprehend the villains. I beg your help in deciphering the following words.
I #vT JLIKIXH KB IXDBLT YBV BD ?QMv X&ME KB NQOXHM BVL NVLL&XK NIWQ&L CYCKMT. I? QvOC NBTM KB vTY OKKMXKIBX KQ#K CBT& UMOLXME IXEIFIEVOUC NOvX ALMOR CVNQ CMNL&NY CNQ&TMC CITWUY AY KOAVUO?IXH N&LKOIX BNNVLL&XNMC BDv U&KKMLC, JQM?QML KQMY #L& MXNIWQML&E BL XBK. QBJ&FML, vI QOF& CBTM IEM#C KQOK JIUU OUUBJ VC ?B NBXKIXVM KB MZNQOXH& IXDBLTOKIBX JIKQBVK #XYBXM AMIXH OJOL& BD I?C T&OXIXH BL ITWBLKOXNM. Uv&? VvC TMMK #K KQ& MXE BD KvQM JMMR OK KQMv DBVXKOIX. I JIUU EMCNLIAM ?QM X&JUY EMFMUBWME NIWQML JQINQ KQMY COY IC NBTWU&?MUY VXALMOROAUM. VXKIU KQ&X, vEB XBvK KLVCK ?QIC NIWQ&L JIKQ #XY IXNLITIXOKIXH &FIE&XNM. KQM RIXH QvOC MYMC OXE M#LC MFMLYJQML&.
[Solution]
Challenge 2
The following ciphertext is believed to have been enciphered quickly using the Vigenére method. We believe the coded message refers to an individual whose codename is JITTERBUG and, most importantly, we know that the message indicates a time and place for an upcoming meeting. We know the city in which the meeting is to take place, but we lack the specific details of when and where this meeting will occur. Other trustworthy sources have indicated that part of the message might refer to a recent incident which took place in Cataluna, Spain. Obviously, spacing and word lengths have not been preserved during the encryption process. Again, we desperately need to know the exact time and place of the meeting in order to apprehend these enemy agents. Time is of the essence on this one.
ZEGXV NDXMU BKZJY YMTUS HTGAT RMIHV
CVYOL IFRAQ HGFIA ENGZK YYXAV XPXFO
FKKPZ XQSGT WVQMJ VOGLP CONIE JUTVO
[Solution]
Challenge 3
Classified documents were stolen from the government during WWI and never recovered. The thief was suspected to be a man by the name of Udall Brown. A change in circumstances has made it more urgent than ever that these documents be found. Though the suspect is long dead, a lead has finally surfaced. Certain documents have come to our attention that we believe will lead to the hidden location of the classified material: A letter and three telegrams to the suspect from a man by the name of Edward. We believe that the key to deciphering the telegrams may lie in some personal shared secret between the two men. The dossier below was compiled about the subject. Your mission is to decipher the telegrams and find the location of the missing classified documents.
Recently recovered letter to Udall from Edward
[Solution]