201210022040 10ujf3

explained decrypted filler

3DES(name+title) ECB, 21 GUIDs, seed 204

Metadata

Post ID: 10ujf3
Title: 201210022040 → 2012-10-02 20:40 on A858's clock
Posted (UTC): 2012-10-03 00:40:43
Timezone: UTC−4 · title 20:40 against posted 00:40 UTC
Author: [deleted]
Account: A858DE45F56D9BC9 main account
Subreddit: r/A858DE45F56D9BC9 the main subreddit
Category: F3 filler: 3DES(name/title) → GUID list, seed known
Size: 1,360 hex characters · 680 bytes
Cipher: 3DES-EDE2 (two-key Triple DES), ECB, PKCS7
Key: MD5(A858DE45F56D9BC9201210022040) = 27aeeeafdee35da75c282b40497deec5 (name+title)
New here: Missing from the community archive; decrypted here for the first time. (new results)
GUIDs: 21
Filler GUID seed: new Random(204).Next(9) ✓ verified
Run: Run 35 (seed 854,622,578) (seed)
Draw: 50 · predicted N = 21 ✓
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: 1 · 0
Tags: automated (decryptable)2012Encrypted masked GUID listarctic-onlykey: name+titlerun: seed

From the post to its content

As posted (encrypted)

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

Read the ciphertext. Strip whitespace: 1,360 hex characters = 680 bytes = 85 8-byte 3DES blocks.
Derive the key. Password = A858DE45F56D9BC9201210022040 (name+title). Key = MD5(password) = 27aeeeafdee35da75c282b40497deec5, used as a two-key 3DES key.
Decrypt. 3DES-EDE2 in ECB mode, then strip the PKCS7 padding. The plaintext is 21 GUIDs as hex (shown below).

Decrypted: GUID list

  1 c37c00d9-c3e9-237d-be57-d1c83351932d
  2 c9757755-d80f-6181-a48c-831574ed536a
  3 0a85a57f-72cd-3e40-a23d-9196a5763ef0
  4 2b4e3aa5-4c95-0272-bf55-13898f04a17d
  5 c9bf9be1-6345-2978-beba-41ff12eca417
  6 e427e66d-3da0-72cf-a9c8-17656d8819e2
  7 41959ad2-4878-2b25-b44c-18f10ae0c95a
  8 80c970cd-bee3-745a-959f-405eee6ef30b
  9 c57b626e-9ae1-10bb-9fad-1710744784d5
 10 af1c52aa-fc3f-42fc-b02f-d544f438a72d
 11 bdba4f5a-19eb-5348-8444-00e5673ebb3e
 12 d3424ee5-13dd-64b7-b0e0-86a2d2b21287
 13 da9971a7-89f2-7f8d-a600-f31f45ed0318
 14 6d76492a-b354-50cb-b89c-7b88b3a51274
 15 3f981880-78db-64b6-b0c4-a3a66254f645
 16 c341502c-4d61-322b-a11a-0f032513766a
 17 9321f7a8-28d4-5dc8-b1f3-0fb1fe850a17
 18 ea2da4c1-f0ee-4935-85a8-62d33ed7281e
 19 ac97bdc7-34b7-1c7c-b116-f78d5297b5e8
 20 56c7d4ec-0b53-25bd-9db9-8c250c9ef76f
 21 2f68b9fc-5a6c-8438-a130-72521f5860ab

Explanation

Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 263027271456756354128. Exactly this sequence comes out of new Random(204).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 50 of Run 35 (seed 854,622,578): new Random(854622578), Next(8,64) per post. The RNG predicts N = 21; the post has N = 21 ✓. 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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