201210031041 10vk68

explained decrypted filler

3DES(name+title) ECB, 15 GUIDs, seed 702

Metadata

Post ID: 10vk68
Title: 201210031041 → 2012-10-03 10:41 on A858's clock
Posted (UTC): 2012-10-03 14:41:18
Timezone: UTC−4 · title 10:41 against posted 14:41 UTC
Author: [deleted]
Account: A858DE45F56D9BC9 main account
Subreddit: r/A858DE45F56D9BC9 the main subreddit
Category: F3 filler: 3DES(name/title) → GUID list, seed known
Size: 976 hex characters · 488 bytes
Cipher: 3DES-EDE2 (two-key Triple DES), ECB, PKCS7
Key: MD5(A858DE45F56D9BC9201210031041) = a7bff5b5b298a8fb81fc4b1e5c2c678d (name+title)
New here: Missing from the community archive; decrypted here for the first time. (new results)
GUIDs: 15
Filler GUID seed: new Random(702).Next(9) ✓ verified
Run: Run 35 (seed 854,622,578) (seed)
Draw: 92 · predicted N = 15 ✓
Machine boot: 2012-09-22 10:16–10:36 (seed = uptime at app start)
Sources: arctic-shift · body from arctic-shift
Links: Reddit · Arctic Shift · JSON
Score · comments: 0 · 0
Tags: automated (decryptable)2012Encrypted masked GUID listarctic-onlykey: name+titlerun: seed

From the post to its content

As posted (encrypted)

44EAF2DA39E25E05 79DDFA9A2F444702 DF0C52E91040D853 EB99DE440F77D482 C625C55241F99BAA 6FF047E3AD83C882 77AAA2434A8CA5D5 971B0C34F32AC639 AF75416A4343154F 2B65ED99078BA164 4388F70817E53AFB 73188CCD8511C8A2 05C691395136E514 D422626426F17B92 A5AD30ACB736AF6E 486B1CCC6B92F59F 3D3D23FB6E2B4D14 864B1068A5AF3993 BE094FB821E9A487 1DDEEC985C22E6D1 CB1FAF597B6AADBC 89F686568E8AC535 9C7E7FF2DBCE10B7 92DBFFE8EA787158 F525A960E541B916 DEA354ED53C9C20C 2D880ECC8AD0A584 27426A8810727C53 1D9F936B7CE36D18 9E59BE9DA795A2BB 1FFF318E7A94A65D D570C90371345867 E694225BD490136B F8929DEEC5B403BD 33A89D05ABC4E520 43F81E67B7F276DC 536D9DBE0DDC61DC C4AEF19AC9B2017B 47F14A1F5B715756 6BD960BE83E62607 7D3E35E8225106BD 0F40FB7CD1CF080D AE5FB71A63A839FD 911A2FB8425D5619 7B434AC009F3D0C8 C1DBED4A1F07322D F82ABA9866514E3B E3821990602C6A62 802CA5D906461184 9E7876FC8D6E5121 46AC7EB5F5E9EA2A F24166C540139F5D 8ED79DC0C0982644 6257D24CA4F03A28 81FB688D902168B9 B1526EB71C9FB3E8 84A02A3368B4D4BF BAB87BC1CBC3B2AB 634551A3AA75A63B F09C2995BB882685 31BBBEFCA4222F21

Read the ciphertext. Strip whitespace: 976 hex characters = 488 bytes = 61 8-byte 3DES blocks.
Derive the key. Password = A858DE45F56D9BC9201210031041 (name+title). Key = MD5(password) = a7bff5b5b298a8fb81fc4b1e5c2c678d, used as a two-key 3DES key.
Decrypt. 3DES-EDE2 in ECB mode, then strip the PKCS7 padding. The plaintext is 15 GUIDs as hex (shown below).

Decrypted: GUID list

  1 af0fe110-c192-40fd-bb37-965b22a5d101
  2 eb6e3961-da40-746b-81b7-b691df519aea
  3 0fde0723-c949-441a-9b33-890d26965720
  4 ea96552a-11ae-3e9e-9532-34f1e8117dcc
  5 8492104c-8c58-1704-976a-3fe6fb288c1d
  6 db9715e9-6e1e-0cd3-b992-ec8fef09511a
  7 adc608b0-312f-3a38-a960-8bd2fdd60f9c
  8 0b45d84f-276b-5a49-8bd1-75a1cfba1b37
  9 cc97d8c6-1452-78b7-86b5-3297481e6b97
 10 4c8e4497-2f97-13ef-ab54-b593a86e6b1b
 11 f2429478-e27f-429c-a9d3-e6c7c4812db4
 12 d368182d-f92b-4259-9037-792f9427e8bd
 13 7d1158d4-3066-2a54-9856-22b8f90a73e2
 14 900a6df5-ac0e-6a44-b5a9-b8c0e3ab8bf5
 15 361d5e92-cc99-33e5-b175-18269608c925

Explanation

Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 474310357144263. Exactly this sequence comes out of new Random(702).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 92 of Run 35 (seed 854,622,578): new Random(854622578), Next(8,64) per post. The RNG predicts N = 15; the post has N = 15 ✓. The seed is the machine's uptime in ms when the app started (boot 2012-09-22 10:16–10:36).
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

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