A858DE45F56D9BC9 archive

201207090943 w9pj0

explained decrypted filler

seed 484

Metadata

Post ID
w9pj0
Title
201207090943 → 2012-07-09 09:43 on A858's clock
Posted (UTC)
2012-07-09 13:42:05
Timezone
UTC−4 · title 09:43 against posted 13:42 UTC
Author
[deleted]
Account
A858DE45F56D9BC9 main account
Subreddit
r/A858DE45F56D9BC9 the main subreddit
Category
F3 filler: 3DES(name/title) → GUID list, seed known
Size
1,872 hex characters · 936 bytes
Cipher
3DES-EDE2 (two-key Triple DES), ECB, PKCS7
Key
MD5(A858DE45F56D9BC9A858DE45F56D9BC9) = 0dcc4bd9e114ebc42078977dc9125404 (name+name)
GUIDs
29
Filler GUID seed
new Random(484).Next(9) ✓ verified
Run
Run 14 (seed 205,976,312) (seed)
Draw
14 · predicted N = 29 ✓
Machine boot
2012-07-05 08:28–12:28 (seed = uptime at app start)
Sources
community-archive, arctic-shift · body from community-archive
Links
Reddit · Arctic Shift · JSON
Score · comments
0 · 0
Tags
automated (decryptable)2012Encrypted masked GUID listkey: name+namerun: seed

From the post to its content

As posted (encrypted)

D3360513C45C8AA1 25EA4159034E4B78 BFB6F0CF512E2DFE 575544EFAA27663F 2D20DE602DEFBF37 C1B83078ADFB58D3 709990C115D4291D 018CC834CD08A9BD EF82BDB414745A78 C409B8F5AA5F3B9E 5126B50BD82B0391 E4BBC1F1BA953B0B 1393CDE576C99251 8E8EF2A8780D4D99 6BFBB28B589BE79B C69F9F8DC23D0EBC 6A03F7D70A5D47A7 5A2D2AA4B9A2FC23 DE8B1FE27B9B269C C22F224BE37384C2 0AF5E01AD60EC448 AA53D1B1F41D84D1 B374877BD06400F5 2C94FA88FEA3CF1F FD46D24D130B70D6 DC990BB43E58048E 61385599B4B22D3B 64322E3C7A17C03C 99485658DB55E798 BFC8986F7EA9D165 DE01A19B217DA116 12D6A66454027D45 68D9EDF69704F4A5 33731DBA38E43B01 DAEEAFCD64329921 21105700DD99D0D3 674266E761722440 B9873490F42213A3 1C0D4F3DEFD938C4 F2B3D7D523E519CC 94D6AA42C0A4F54D 4986C997AC718D25 8F146AB9BFED94F5 CDAF25C48E926A6F A5D5975376DE23FF 4917CF6088D52D19 4E5833C2381C760E DFB74AAA37C2406C 8979F9A7A474BA5A EBF1E36DBDB92898 7A12B204123B92FB 9E4937FBBD404023 46A9415307BABAEA C409B129AFF91360 AF36C3C7495909E9 9CA29D8E201F22F0 74245B450286E628 E3C7AFFB35E02EDE A9BAF07BEFC661EB 8C039FD55AFF52DC 52FECFBE3A579813 FDE1A1A54580953B D06C5894E4478D8D 463A9B1107F6D617 363B804001A9AE84 16896C88BC9BDEAC 4C06289E51053283 9AEE94327F3B7CCD 2A23EC9CAF9755A6 13486C5AAA300261 FD079F057CDDE97A ECA78E5C865F2430 7B2BCAF03E37721C 5B68EB76EAA823BB B5146F87E1936C67 88E6B367615E7455 445507B45ACACEF9 86CB9F2AD4577E77 E6B73E42032FC95B 5C693883C318974D D467EBB2683D6FBA A23429D46965E708 C603BF666AFADFD5 845CDCB5B094E0D3 AF8CE6C2A3DB389F 1DA31574AC813595 90373304E61E1CD7 99B4F39448B41A02 0778D77572CA1E7A A630488F6A129BD1 4EAC5EA44DF8611B D30B5589947C1843 F1C72103DE8D5349 B90EC05242750DB0 48744F0C62D7B6F1 A8FC8FD4DF146384 5FDBCB5F9C456233 1289B84F5853E34E A15B0FB8CF5FA000 002730AD3621F4F1 48616EFB7861D48F 8DA954071CD3F24E CD6D5B819479B140 9DA1B9745845815B 269D2B93E9AFF875 0B2C909F54C6FBC5 D239B8C5ED4D50BE D641931187BDC88F 93E43A114B267970 54DF73A7C234C2B0 7B3A81221955009D 2BB0C631F8B225CF 8777F58879EDA7C8 59FC5221B7D68A32 540139A1B1AE89AD 9540C1AE7345C754 12ECFFDF2899BD4C
  • Read the ciphertext. Strip whitespace: 1,872 hex characters = 936 bytes = 117 8-byte 3DES blocks.
  • Derive the key. Password = A858DE45F56D9BC9A858DE45F56D9BC9 (name+name). Key = MD5(password) = 0dcc4bd9e114ebc42078977dc9125404, used as a two-key 3DES key.
  • Decrypt. 3DES-EDE2 in ECB mode, then strip the PKCS7 padding. The plaintext is 29 GUIDs as hex (shown below).

Decrypted: GUID list

  1 405dc69b-756e-57a7-8a45-8b34ab592d55
  2 4d6255b1-b7a9-7de0-8757-f16ab81a7aeb
  3 b3d0495e-9737-0a82-bba0-f0bd1a7f0157
  4 f0aedd93-950e-7a48-942b-16333ca1074c
  5 7b0d7fb6-a26e-6dff-9f20-465358e856e5
  6 fd4c882e-242b-494a-94dd-b225fbfbf0d7
  7 e75c2c27-a8f3-6b5a-bd06-a2dd082a84da
  8 aa64962e-f838-2b57-94ad-b923da66f3fd
  9 33ac6d78-b6a9-7540-acf7-c25b5fbe68d4
 10 96f9528f-8b34-6a87-a7f1-8a36b2230605
 11 ffd994ae-2d3a-708c-a448-cc389295e88e
 12 04269e00-b4a1-2c20-8e70-defc0f87bd04
 13 af485efd-a2e5-3120-8d30-ea1c700b9d7b
 14 7c4ec1dc-4101-2de3-8ddd-30293979b193
 15 3cfd0370-1bb2-689a-8669-5ece010965f3
 16 27f12c03-4c3d-29f8-838d-e7ebc82945b7
 17 350a76fd-45b8-272b-bd36-4e0f926a35e6
 18 eecadb75-81ea-044b-8fac-c8d26919ffd9
 19 4ec31fe3-e836-7a2d-8fe8-d48ae99b0526
 20 910904cf-c62f-6c33-be97-acf59831538f
 21 09476b1a-d2b7-193c-9889-4fa5414469e0
 22 37b909eb-f004-5fb3-ab0b-758c764e18ef
 23 25fdd696-6afb-7d51-a69e-77fd3f8b56c1
 24 cf16fec6-1065-1030-ac42-e9dde4ce809b
 25 bd33206a-a7da-1395-9a25-79a3e19ea66e
 26 5f9ace82-e330-7945-b2eb-83576436c7d5
 27 9942d83a-8ee2-0e52-8635-d68ce3f6ef13
 28 d986c4a9-cbee-5d8e-af39-e00e61bda2b9
 29 022d1172-9a11-2fc2-97cd-dcb26efb85f5

Explanation

  1. Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 57076462767232622076157117052. Exactly this sequence comes out of new Random(484).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.
  2. Explain the count. This post is draw 14 of Run 14 (seed 205,976,312): new Random(205976312), Next(8,64) per post. The RNG predicts N = 29; the post has N = 29 ✓. The seed is the machine's uptime in ms when the app started (boot 2012-07-05 08:28–12:28).
  3. Conclusion. Filler. The content is fully explained by the two RNGs.

Related

Findings: Mask digit · Count RNG & runs