201210051103 10ztp3

explained decrypted filler

3DES(name+title) ECB, 21 GUIDs, seed 278

Metadata

Post ID: 10ztp3
Title: 201210051103 → 2012-10-05 11:03 on A858's clock
Posted (UTC): 2012-10-05 15:03:15
Timezone: UTC−4 · title 11:03 against posted 15:03 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(A858DE45F56D9BC9201210051103) = ae0235d4b3892ab6167e339e5960c6c2 (name+title)
New here: Missing from the community archive; decrypted here for the first time. (new results)
GUIDs: 21
Filler GUID seed: new Random(278).Next(9) ✓ verified
Run: Run 35 (seed 854,622,578) (seed)
Draw: 237 · 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 = A858DE45F56D9BC9201210051103 (name+title). Key = MD5(password) = ae0235d4b3892ab6167e339e5960c6c2, 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 0c2620ec-4efc-834d-b039-30dffe2b8eb7
  2 fa1f69b7-e1f2-3225-bf69-455d77719a08
  3 c59f25fa-5eac-03fd-8dc0-7bb432f400d2
  4 40bdfd5b-4018-8ab2-bec5-f23f93ddf4c8
  5 e1d42a64-f165-6f83-98ef-cd4294239882
  6 226f7d5b-4433-447e-b394-f85063ba3ed9
  7 2a180f71-059d-438d-9276-2fc944e7b7d3
  8 4f3fbe6d-dac7-89d5-a7e6-09ecc0cb294d
  9 7165ccbb-8eb7-3e4a-b822-e7bcd27b1bc7
 10 9e966566-4d3c-79ff-8ddf-bfc0c28a995d
 11 d335da50-8e76-0bc8-ad6d-dcd518f6ad34
 12 34387b45-3481-4856-a752-c93b7290a3f5
 13 55b9b118-b760-656f-a190-53425ad1f0bb
 14 0aeb1d0b-511f-0b06-996d-73b52b444234
 15 2bf34e65-528f-55c7-81f9-f6fd1ec17d29
 16 d1456c85-6604-5ca7-a606-b93e6df326ae
 17 96afe47d-4f94-6f68-b6b9-a79be214689a
 18 bc661e26-f689-38b6-b822-087776c62b3d
 19 8aea9c39-6dd2-1215-948c-022228527b1b
 20 13554f26-487e-8094-8bea-9cbc1f376c09
 21 cd6169d5-ea0d-644a-abf6-925c5e891982

Explanation

Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 830864483704605563186. Exactly this sequence comes out of new Random(278).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 237 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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