201210110500 119pai

explained decrypted filler

seed 212

Metadata

Post ID: 119pai
Title: 201210110500 → 2012-10-11 05:00 on A858's clock
Posted (UTC): 2012-10-10 20:00:37
Timezone: UTC+9 · title 05:00 against posted 20:00 UTC
Author: [deleted]
Account: A858DE45F56D9BC9 main account
Subreddit: r/A858DE45F56D9BC9 the main subreddit
Category: F3 filler: 3DES(name/title) → GUID list, seed known
Size: 1,488 hex characters · 744 bytes
Cipher: 3DES-EDE2 (two-key Triple DES), ECB, PKCS7
Key: MD5(A858DE45F56D9BC9201210110500) = 90ebed72c913f13b4891c33057c23d07 (name+title)
GUIDs: 23
Filler GUID seed: new Random(212).Next(9) ✓ verified
Run: Run 35 (seed 854,622,578) (seed)
Draw: 534 · predicted N = 23 ✓
Machine boot: 2012-09-22 10:16–10:36 (seed = uptime at app start)
Sources: community-archive, arctic-shift · body from community-archive
Links: Reddit · Arctic Shift · JSON
Score · comments: 5 · 0
Tags: automated (decryptable)2012Encrypted masked GUID listkey: name+titlerun: seed

From the post to its content

As posted (encrypted)

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

Read the ciphertext. Strip whitespace: 1,488 hex characters = 744 bytes = 93 8-byte 3DES blocks.
Derive the key. Password = A858DE45F56D9BC9201210110500 (name+title). Key = MD5(password) = 90ebed72c913f13b4891c33057c23d07, used as a two-key 3DES key.
Decrypt. 3DES-EDE2 in ECB mode, then strip the PKCS7 padding. The plaintext is 23 GUIDs as hex (shown below).

Decrypted: GUID list

  1 a8619b33-a584-425a-b177-e9e1bdb0289c
  2 f5a75bc6-5af5-00a1-85b2-0d2141ed7209
  3 760cd468-869d-8070-91ee-7688b94c94b4
  4 ffb22546-e383-7004-8b08-12595b253967
  5 ab0accf1-07c9-8328-97ff-451ba00f6a2c
  6 9394f550-7049-7947-bdbb-7fc8aad8d87c
  7 2fa15a3b-f1a1-88d6-af82-67b316a90454
  8 ee996846-448a-786c-956c-e4de462d96d2
  9 428f0925-8678-1013-a10a-b512d7e4ac18
 10 a181ea8a-771f-4d8f-894d-135c3e232bf0
 11 8b46619e-7151-4e9b-9f64-1959c595929c
 12 ba301570-555b-86a6-969a-ec278fe4c49c
 13 24b35592-cfce-301a-a0ae-a4da11e57453
 14 d10093a5-ffce-6578-9b67-fde7eb3121e2
 15 e2d378c4-d1e3-3119-ae10-f113cf487caa
 16 4216bce0-a5a6-3056-9c18-eaeeb6390e5f
 17 65bbe2d9-0ea0-8c97-b0ce-566b95b1888f
 18 a9034e78-23ff-32a9-b990-ec667c98569b
 19 d27c13b6-0687-398a-86fc-971653e49c26
 20 14b8264f-8bae-39a1-9ff6-7795eba452f7
 21 e3ed70de-631c-8a5d-a0a1-12d05ee966e0
 22 3f078727-028c-7d53-88b2-41c69a383af5
 23 4c50d98b-40b6-7b86-8217-0546e95e0787

Explanation

Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 40878787144836338333877. Exactly this sequence comes out of new Random(212).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 534 of Run 35 (seed 854,622,578): new Random(854622578), Next(8,64) per post. The RNG predicts N = 23; the post has N = 23 ✓. 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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