This challenge closed on 06/11/2019. See below for the correct answers.
Practice Challenge 3A, Alarm bells ring
X msdjru je ar trhjsxd jwr beij Sfebbe Jrd hrfehj hrsbbp msid’j sd sttxurdj ie X sizru shtwxlri je irshtw jwr cxiixed fsfrhi xd tsir jwr ehxvxdsb hrfehj wsu arrd cxinxbru. Jwrp irshtwru rlrhpjwxdv sdu tekbud’j nxdu xj akj jwrd iecredr wsu s ahsxdmslr sdu twrtzru jwr Sfebbe rbrlrd nxbri. Je rlrhpedr’i hrbxrn jwrp nekdu xj jwrhr sdu jwr shtwxlxij hrtzedru jwsj iecredr vej uxijhstjru. Mxjw jwr lebkcr en cxiixed fsfrhi jwrp shr wsdubxdv jwxi xi dej s ikhfhxir, akj vxlrd jwr xcfehjsdtr en jwrir uetkcrdji xj xi s axj sbshcxdv sdu uerid’j nrrb bxzr jwr msp DSIS kiksbbp ueri jwxdvi. Sdpmsp, jwr nxdu iwekbu wslr hrsiikhru cr, sdu xj mekbu wslr xn X wsud’j beezru ie tshrnkbbp sj jwr nxbr. Rlrhpjwxdv beezru nxdr rotrfj jwsj jwr mehu Xdyrtjxed xd jwr frdkbjxcsjr fshsvhsfw msi ifrbj mxjw sd X. Pek csp dej ar ikhfhxiru, akj xn pek beez sj jwr urthpfj en jwr csdvbru lrhixed xj xi cxiifrbj bdyrtjxed, mxjw sd b hrfbstxdv jwr X.
X mekbud’j wslr dejxtru akj X wsu urthpfjru jwr ehxvxdsb ap wsdu sdu msi ikhfhxiru ap jwr jpfe. Xj ijktz xd cp cxdu ie mwrd X ism jwr nxbru lrhixed mxjwekj xj jwsj hsdv sbshc arbbi. Edtr mr ijshjru xdlrijxvsjxdv mr betzru kf jwr tecfkjrh nxbri ie X tsd edbp siikcr jwsj jwr nxbru lrhixed msi jhsdithxaru ap iecredr mwe dem wsi sttrii je jwr fhxdjru lrhixed akj mwe uerid’j wslr jwr tbrshsdtr je sttrii jwr ehxvxdsb. Jwr gkrijxed xi, mwp mekbu jwrp fheuktr s drm lrhixed? X tsd edbp jwxdz jwsj jwrp msdjru je wrsu enn cehr xdlrijxvsjxed ap vxlxdv ki s hrsied je jwxdz xj msi sbb s cxijszr snjrh sbb. Xn jwsj msi jwr fbsd jwrd xj wsid’j mehzru. Xj irrci tbrsh je cr jwsj iecredr hrsbbp ueri wslr iecrjwxdv je wxur.
X twrtzru jwr irtkhxjp tbrshsdtr bxij sdu jwrhr mrhr jme wkduhru sdu jwxhjp-irlrd frefbr mxjw sttrii je jwr shtwxlr heec mwrhr mr shr ijehxdv jwr xdlrijxvsjxed nxbri mwe ue dej sbie wslr tkhhrdj sttrii je jweir tecfkjrh nxbri. En jweir, edr wkduhru sdu rxvwjrrd uxu wslr jrhcxdsb sttrii arnehr mr tbeiru xj uemd, ie jwr ikifrtj bxij xi iwhxdzxdv, mwxtw X ikffeir xi iecrjwxdv, akj X mekbu fhrnrh je dshhem xj uemd s axj cehr. Mxjw jwr bskdtw en Sfebbe Jmrblr tecxdv kf droj cedjw jwr ceeu xi vrjjxdv jrdir sdu X mekbu hrsbbp bxzr je cszr ikhr ekh cxitwxrn cszrh uerid’j wslr sdp cehr ikhfhxiri xd ijehr.
Je cszr csjjrhi mehir X wrshu jwsj jwr wsmzi sj jwr Frdjsved shr vrjjxdv hrijbrii. Tekbu pek vrj elrh jwrhr sdu nxdu ekj mwsj jwrp shr jwxdzxdv? Vxlrd jwsj ekh jehcrdjeh irrci je wslr fhrjjp wxvw-brlrb sttrii, cspar pek tekbu thsdz kf jwr irtkhxjp ed ekh tecci? Cspar s zrpmehu txfwrh abetzru si ijsdushu?
Correct AnswerHarry, I wanted to be certain the lost Apollo Ten report really wasn’t an accident so I asked archives to search the mission papers in case the original report had been misfiled. They searched everything and couldn’t find it but then someone had a brainwave and checked the Apollo eleven files. To everyone’s relief they found it there and the archivist reckoned that someone got distracted. With the volume of mission papers they are handling this is not a surprise, but given the importance of these documents it is a bit alarming and doesn’t feel like the way NASA usually does things. Anyway, the find should have reassured me, and it would have if I hadn’t looked so carefully at the file. Everything looked fine except that the word Injection in the penultimate paragraph was spelt with an I. You may not be surprised, but if you look at the decrypt of the mangled version it is misspelt lnjection, with an l replacing the I. I wouldn’t have noticed but I had decrypted the original by hand and was surprised by the typo. It stuck in my mind so when I saw the filed version without it that rang alarm bells. Once we started investigating we locked up the computer files so I can only assume that the filed version was transcribed by someone who now has access to the printed version but who doesn’t have the clearance to access the original. The question is, why would they produce a new version? I can only think that they wanted to head off more investigation by giving us a reason to think it was all a mistake after all. If that was the plan then it hasn’t worked. It seems clear to me that someone really does have something to hide. I checked the security clearance list and there were two hundred and thirty-seven people with access to the archive room where we are storing the investigation files who do not also have current access to those computer files. Of those, one hundred and eighteen did have terminal access before we closed it down, so the suspect list is shrinking, which I suppose is something, but I would prefer to narrow it down a bit more. With the launch of Apollo Twelve coming up next month the mood is getting tense and I would really like to make sure our mischief maker doesn’t have any more surprises in store. To make matters worse I heard that the hawks at the Pentagon are getting restless. Could you get over there and find out what they are thinking? Given that our tormentor seems to have pretty high-level access, maybe you could crank up the security on our comms? Maybe a keyword cipher blocked as standard? Meg
Practice Challenge 3B, Treading softly
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