201210031201 10vpb6

explained decrypted filler

3DES(name+title) ECB, 18 GUIDs, seed 678

Metadata

Post ID: 10vpb6
Title: 201210031201 → 2012-10-03 12:01 on A858's clock
Posted (UTC): 2012-10-03 16:01:21
Timezone: UTC−4 · title 12:01 against posted 16:01 UTC
Author: [deleted]
Account: A858DE45F56D9BC9 main account
Subreddit: r/A858DE45F56D9BC9 the main subreddit
Category: F3 filler: 3DES(name/title) → GUID list, seed known
Size: 1,168 hex characters · 584 bytes
Cipher: 3DES-EDE2 (two-key Triple DES), ECB, PKCS7
Key: MD5(A858DE45F56D9BC9201210031201) = 39986b625fc08068c2a2f76096ea6d3d (name+title)
New here: Missing from the community archive; decrypted here for the first time. (new results)
GUIDs: 18
Filler GUID seed: new Random(678).Next(9) ✓ verified
Run: Run 35 (seed 854,622,578) (seed)
Draw: 96 · predicted N = 18 ✓
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: 2 · 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: 1,168 hex characters = 584 bytes = 73 8-byte 3DES blocks.
Derive the key. Password = A858DE45F56D9BC9201210031201 (name+title). Key = MD5(password) = 39986b625fc08068c2a2f76096ea6d3d, used as a two-key 3DES key.
Decrypt. 3DES-EDE2 in ECB mode, then strip the PKCS7 padding. The plaintext is 18 GUIDs as hex (shown below).

Decrypted: GUID list

  1 483948f3-74d7-8eaa-ac98-918548e855c6
  2 b44b75df-d9a4-6f63-85e1-e2b8a5c17954
  3 e67bf984-348c-6509-a110-f49d88155944
  4 873ee9ca-e817-20c7-9fdf-661c4b8bfdc6
  5 edaa72ae-a478-2716-99f4-de0ceb0ebbd7
  6 06a21b7f-c81b-078e-b6ed-c41d44e59295
  7 dec9efbc-4944-6bff-9020-4761e371cbad
  8 f8e174fb-1393-5d1e-b573-9134b22b1aba
  9 635c4ac6-2d35-7cc0-bb38-b47fb5321481
 10 722fab28-3730-2dd3-957c-b29e5cb8a8b0
 11 bbfbbedc-8c83-715a-b4d1-7173a83a6444
 12 6bad4d3c-c1c8-7678-b07d-efe516a8c9e2
 13 661897bf-c810-6ae8-9bff-955a887c85d6
 14 1e9bda18-f1c7-11b2-b70c-c7364d006501
 15 45cb7dae-eec1-5053-9d24-898ac81f6d2f
 16 6d8db9b8-a16a-4d4d-8fbb-5ad62dba4c48
 17 a8b7e3c7-c553-7437-aea8-6abba91a50b7
 18 0e2a170b-0aaa-3276-8ea2-62181fad21c5

Explanation

Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 866220657277615473. Exactly this sequence comes out of new Random(678).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 96 of Run 35 (seed 854,622,578): new Random(854622578), Next(8,64) per post. The RNG predicts N = 18; the post has N = 18 ✓. 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

Related