201207080136 w6kv1

explained decrypted filler

seed 266

Metadata

Post ID: w6kv1
Title: 201207080136 → 2012-07-08 01:36 on A858's clock
Posted (UTC): 2012-07-07 16:34:23
Timezone: UTC+9 · title 01:36 against posted 16:34 UTC
Author: [deleted]
Account: A858DE45F56D9BC9 main account
Subreddit: r/A858DE45F56D9BC9 the main subreddit
Category: F3 filler: 3DES(name/title) → GUID list, seed known
Size: 1,296 hex characters · 648 bytes
Cipher: 3DES-EDE2 (two-key Triple DES), ECB, PKCS7
Key: MD5(A858DE45F56D9BC9) = 34a14a42e98ff96095af56604e290cae (name)
GUIDs: 20
Filler GUID seed: new Random(266).Next(9) ✓ verified
Run: Run 11 (seed 37,057,156) (seed)
Draw: 39 · predicted N = 20 ✓
Machine boot: 2012-07-05 09:16–10:46 (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: namerun: seed

From the post to its content

As posted (encrypted)

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

Read the ciphertext. Strip whitespace: 1,296 hex characters = 648 bytes = 81 8-byte 3DES blocks.
Derive the key. Password = A858DE45F56D9BC9 (name). Key = MD5(password) = 34a14a42e98ff96095af56604e290cae, used as a two-key 3DES key.
Decrypt. 3DES-EDE2 in ECB mode, then strip the PKCS7 padding. The plaintext is 20 GUIDs as hex (shown below).

Decrypted: GUID list

  1 7452d639-7a5d-68ac-92eb-0112f365a9b9
  2 dfff4270-15a4-7f97-b162-29453531cebe
  3 9edf4be3-8236-68db-905c-10256b7b5cb7
  4 025d60ee-1038-37b1-b70d-7568193c9f15
  5 c661e025-6eb6-2ef8-a6c5-bd4f8a2520b0
  6 ccd88405-26ed-0e22-b41f-f355b6667a56
  7 487a19b6-818d-0058-a1ed-0cfd0a784fd1
  8 775564ae-4dff-8da0-8c58-f62d5313bdfb
  9 2b0b2847-0671-7ff5-9844-6f3a36b2e174
 10 773b2a12-5370-3cb5-80ed-9f7ee14afd4e
 11 d9ffe5b8-7607-2023-8518-6ed71cf7d95b
 12 83afde3c-96b0-1eff-b621-7db799a5def1
 13 d8609984-f7d4-4604-943f-2d05c7c76fb0
 14 c8f71036-c700-705c-9c22-1ac897ed635b
 15 ef866060-faf9-1922-84d7-bc136ffc239f
 16 90a0aed5-ad3a-13fe-a217-6fa50321998a
 17 d74dda63-9687-6351-8a4d-4e7bfa5d6853
 18 a094d88e-c98f-8fc4-8c00-35a8bb7ee031
 19 7acb5596-a27e-7ff0-8798-e36c0318456a
 20 28ee4b4d-65cb-2a16-acb7-b045b4fe85c7

Explanation

Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 67632008732147116872. Exactly this sequence comes out of new Random(266).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 39 of Run 11 (seed 37,057,156): new Random(37057156), Next(8,64) per post. The RNG predicts N = 20; the post has N = 20 ✓. The seed is the machine's uptime in ms when the app started (boot 2012-07-05 09:16–10:46).
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