201305201207 1eob7d

explained decrypted filler

seed 75

Metadata

Post ID: 1eob7d
Title: 201305201207 → 2013-05-20 12:07 on A858's clock
Posted (UTC): 2013-05-20 04:07:56
Timezone: UTC+8 · title 12:07 against posted 04:07 UTC
Author: [deleted]
Account: A858DE45F56D9BC9 main account
Subreddit: r/A858DE45F56D9BC9 the main subreddit
Category: F3 filler: 3DES(name/title) → GUID list, seed known
Size: 3,088 hex characters · 1,544 bytes
Cipher: 3DES-EDE2 (two-key Triple DES), ECB, PKCS7
Key: MD5(A858DE45F56D9BC9201305201207) = 057039a97d7a3cb7e044f265b2f2e891 (name+title)
GUIDs: 48
Filler GUID seed: new Random(75).Next(9) ✓ verified
Run: Run 46 (seed 39,043,781) (seed)
Draw: 42 · predicted N = 48 ✓
Machine boot: 2013-05-15 03:07–10:31 (seed = uptime at app start)
Sources: community-archive, arctic-shift · body from community-archive
Links: Reddit · Arctic Shift · JSON
Score · comments: 7 · 0
Tags: automated (decryptable)2013Encrypted masked GUID listkey: name+titlerun: seed

From the post to its content

As posted (encrypted)

86EAE7705B1E1408 7F73FE45FB0D7304 8F4D9C91F07C19DB 0599C1022EA92DCD 87BBC42C31A12362 7B920C9741A44700 A70A9CF58A7AA9D3 0E46A4FB78CB0FC2 E0D53B1626C28AF6 6FC78A36FF09F98B 5047CCE232E94DC6 54B36FCFE1172064 E3083F95B7BF1C81 3CBB16DC299DA2D6 75428383093125ED 60387DDEEAC087CD 4DFD28EC687EA51C 7D957BBA0ADB7E90 ABCF5FB165E14298 CDA5360170644E2A 8FE1D2FC7B2F511E 91680EBDA5642967 151CE7AC55D7D972 0B55A4BF743CC659 21E59F73BCF099DD 1A292A4A5E9D344B EF355600EA5C583A CE9A386910E2EEE4 B8F8FCA759F4A1CF 60B4626515678D13 B6457012B592317C 91757B11C9779412 0A5423D769954370 BD1795491ED5BA8E 025774715DECFAE0 E833A94AC3E28D48 FE225AA88F4A8F50 BE5E091CF2C1DA8B E9284C68EE572070 5194E9D7F0B23020 7F5580AAD9D7D785 5FE3B6A1E4B258E2 80497662355BB197 F9684E40EC33CBF3 C9103BAF21A5A1BB DF3C7CC5329F690B D3CBB09BD1D65261 6BEB33253462AB7F 49087516117573AF 4F9AC4A84E86F7EB 254BDE930FFB0DF7 D09617E58B8DC4C7 7C4139CF062C607F E0F8922CEE6D48C5 250C5C9FF0FF6C75 44F9E632CFCCF2F7 D0875A654E856ECE DD40706914CC716E A6945CF8D7FEC8EF 13B3650D0AAB7B4E BD7AF2AEF72D382D 07CC163FF52B1E9F 936BF2157949587B 0D486973F534CA52 D22B53F570404F89 6EE50FA79E006DBE 29647D8A1E6EDAA6 4AFCD370CFB82D70 E4D7BA092F763D31 55F0BB0BBE214975 7801648047572EE4 195B4D1017C1A5CA 0F205B88BB725EFD F7D9DDEAC3D15209 2CD0607812D5838D D5272142CBB9F6F1 1B1865AADEE2EB8D 12D497C9B2752261 59C3D6F4A98AFEA6 A2752D68F156E2E0 4EFD373A5370158C 589855E49E6DB4C4 CAC220F5EF5FE882 29B0E4837AF2A6DF B62C59C7BEF82D7A D747CF876F239E46 B24659CE0A9292BB 6D675976CDF3C026 AC588FCB2D6C262D 2916B262B138B687 09E80C379FA85044 4080E58C63370B49 B6C4B0CF25801F16 721C1B57F6EA0D85 D12115444A119E50 2B5D9F68E08737C0 F694FACC48A8C149 1F9027F3B15F4CC0 CD1A62D34F368129 809955054F32172C B26272FEFC67A98F 05D16F450ABCBE23 BBC38EF58BDD15CB 786EEAF121262C5D 551507F7168BBC72 F4D830837CCF2938 F70480553C5BB2AB AC68EAAC7779A525 5B2B472BA5DF4A4B 74AF8C2A5F4A0A07 63D765F7990D38CD 9F3600263636ED39 F79E09ABCA362F75 08779A862569A582 71523C2B1A979062 8CE9BED590460E49 2EA27B680C32E996 0937E1EE37445E70 F5F4DFE2D60D54A3 92D54390CF9CEAC5 15E0B7FDA0213306 A19AF93CFE385CB5 7FAC57A50407C6D8 C3B8137C7024E1A0 1F3813B09FEB81EA 10B0A567ABF0F324 702D0A0CC171A7D8 32E8D552B5BACCF7 598F32C672D97ED3 8E01EB270E89639E 4CA60EBE309CA0CA 912587A8D5A1185B 0DD25057E971D476 D0A521EBE4690391 7BEFB5BB67FCE55C 802CA8D97E2C3BF6 6C99CA5CAEB9A7D1 AAD814787E0C749B 89029590395A734D CAA2BF82D457CC2B 94E30CA58410F3DA 7F4E351E6810FB3B AD64FA7478260371 35793481F498E950 2E3DAD158DE1A016 42F97F523990712A BE3215767ED55CA7 406A517ABB047164 139945BC565D7FEF 047EFE7B8D6082D1 3CEC7AE6ECDD463D 448D16554A9451D3 2BE01282DAA494AC 0EFA3668591F6C27 7429607713EB9188 C82EA5EB3FD7647B E6AD0EA8E0BCCA1F 5F7A5400696A5688 34FC28BDDB4163A7 9D6AE7D9AC8570A0 EC1E5443E563F4EF BC06C41409640761 5E5945B5850F15B9 560F6A206DAAD7E6 663A5A4E37A50568 85916059837CF1CE 534788894E6D37B2 6F23E77A3FA8074B EA24687200AFA74F 74AE17285BF42FBC D5D579924C66E9D1 7C17B0BBB3A37087 F4790DC0FFA627A2 4B11724F7E8EAE9D 124FA102126C8A27 0A12342D1DDB73DB A6C8675A8BF2B8E0 3AFD5EF5B33ACFC1 68E30B59C3DAB1F5 E60A05349329ED2E 2B1559A7155BE347 58D5FE6B08C18DD4 CFF8F8FF24AAE326 2BBED8DDC814B433 119B8831490C485E 44C697D01A150B7B 77B0D84A7AD3FAC3 AE3082DBEF340075 7C833B711CF04CA7 16AB98FEA13A9EF5 CACA09795A0112FE CAA0ACA66710E9B3 7DAA37895256FA93

Read the ciphertext. Strip whitespace: 3,088 hex characters = 1,544 bytes = 193 8-byte 3DES blocks.
Derive the key. Password = A858DE45F56D9BC9201305201207 (name+title). Key = MD5(password) = 057039a97d7a3cb7e044f265b2f2e891, used as a two-key 3DES key.
Decrypt. 3DES-EDE2 in ECB mode, then strip the PKCS7 padding. The plaintext is 48 GUIDs as hex (shown below).

Decrypted: GUID list

  1 e65d2800-5924-8a4c-a5ae-0428cfbda539
  2 8fc63f53-3e1d-7be8-8b88-31d63218bcbe
  3 e849442e-3526-19b1-a622-17c924a73a5f
  4 beea07d1-2990-537e-903c-2e718d74eba4
  5 1c6879e4-427a-0490-a028-7a3c55e0029f
  6 f37eab1c-10bc-0962-873d-5c19c8498e6f
  7 7c6897b5-7b51-474c-9ee3-56588ed9ae8a
  8 9c13e5d0-aa9f-0907-ae95-0353d9a257da
  9 e37e69a7-4429-21d8-b844-ad5a2708cd3b
 10 2212ad37-09e7-8367-aa93-fa0462f6d123
 11 e1080615-7a42-49c3-943f-474b4bd77777
 12 081cadd9-b9dc-0b2e-9d10-5a16713cbd3c
 13 53587e78-7fc3-1f4c-bd6d-681f7b759445
 14 844922c0-2631-4a24-b99a-be263329297f
 15 d9198b29-4af5-49cf-947b-6b9895f5c866
 16 7919b99a-dc41-745a-aab5-88d78ed49181
 17 a7a8eb96-34bf-3bd6-ab9c-21212990abfc
 18 b5e3f25f-3b6a-41d2-8a9e-1f157b4a2b22
 19 3d627bcc-7ef8-69e7-8fd9-5b151de3ec74
 20 152d9e69-987a-37a8-94b7-c2805d54aa91
 21 47424dcf-f364-70e6-a7f8-f59ef543177a
 22 81ce8801-2fbf-2827-a58a-1e348498b466
 23 589da0dd-34cc-6456-aa8a-b5bb01436b8a
 24 4b47b8d2-5653-247c-93c2-b705ceac95c5
 25 073871f0-1bca-0a75-8b1a-b115a028de0e
 26 69dec18b-e1ac-676f-b3f6-31ad78f143c8
 27 d500674e-7c8e-3f77-bb30-497d81792399
 28 fc69796c-f89f-1ee8-a366-8bb6a441f5d1
 29 6994e42e-59d8-283f-a334-f7cd7c1509a9
 30 ebe29bd0-e979-464a-ab36-00c3c4131e6e
 31 340a7985-2109-7d37-95ad-db1a83e043e3
 32 a6d93e99-8cee-1997-a14c-80f8491e27ab
 33 e572326f-3ba1-4c0a-a433-f182000faf92
 34 7296372f-ce6d-762a-8e4b-77a9a7230774
 35 cb15ba77-dd45-7288-b2f2-addb5f72986f
 36 c047b353-cc0f-0138-b165-d10b2371a19e
 37 8091165d-1b01-11ca-8eba-6dc9e5deb77a
 38 62bca233-af82-4e22-b937-35ab3a06228e
 39 83b68f10-0016-1c29-8568-f3dccc49149c
 40 5c08fde8-f49f-48e2-ab67-a1ee63c3bc58
 41 5bb2914e-eaf1-0551-8f70-e097ddf26fdf
 42 93ff957d-56b3-4f81-834e-b272bca500c6
 43 86c95e7d-6f0e-0a86-a9de-ccd7eb72ff20
 44 d362f3b3-ed12-6136-ad57-61bfad8d8b50
 45 ebcc6b58-a030-440b-ba7c-945c799ef877
 46 5c4bf086-bb76-7127-9e66-c8456053ec14
 47 f0d34d70-561f-7957-8a43-af3adb72e00d
 48 97bd3db4-7ffa-5de0-a2af-ffbfb38dfc70

Explanation

Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 871500402840144734637262063124714770141404064775. Exactly this sequence comes out of new Random(75).Next(9): the per-post millisecond seed of the mask generator. The other 30 hex digits of each GUID are Guid.NewGuid() output and carry no message.
Explain the count. This post is draw 42 of Run 46 (seed 39,043,781): new Random(39043781), 4·Next(8,16) per post. The RNG predicts N = 48; the post has N = 48 ✓. The seed is the machine's uptime in ms when the app started (boot 2013-05-15 03:07–10:31).
Conclusion. Filler. The content is fully explained by the two RNGs.

Metadata

From the post to its content

As posted (encrypted)

Decrypted: GUID list

Explanation

Related