201208310059 z4cv7

explained decrypted filler

3DES(name+title) ECB, 18 GUIDs, seed 569

Metadata

Post ID: z4cv7
Title: 201208310059 → 2012-08-31 00:59 on A858's clock
Posted (UTC): 2012-08-31 04:59:02
Timezone: UTC−4 · title 00:59 against posted 04:59 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(A858DE45F56D9BC9201208310059) = 07b6af53450e655cb25914eb87d9a823 (name+title)
New here: Missing from the community archive; decrypted here for the first time. (new results)
GUIDs: 18
Filler GUID seed: new Random(569).Next(9) ✓ verified
Run: Run 27 (seed 1,337,299,625) (seed)
Draw: 7 · predicted N = 18 ✓
Machine boot: 2012-08-15 10:07–10:24 (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: 1,168 hex characters = 584 bytes = 73 8-byte 3DES blocks.
Derive the key. Password = A858DE45F56D9BC9201208310059 (name+title). Key = MD5(password) = 07b6af53450e655cb25914eb87d9a823, 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 6262fbfd-9e2e-89fc-a21e-7cf76f8892a9
  2 a1196b6f-1d86-65bd-838e-e7b1903314b4
  3 c4e5c4f3-10dd-42ee-bae6-6a38f37336d0
  4 236ccc57-3bd1-0486-acb9-f93a9dcee062
  5 709799eb-c455-00ff-a657-a4eb7e110ae3
  6 3c02e73f-88a2-7197-bebf-0813c04f90f9
  7 13ebffab-3f3f-7583-880a-38cd9d66525d
  8 16ed7abf-2fed-88c7-a4b7-ad4d63114d0d
  9 b2c31306-551f-371f-87ce-aea4f36db060
 10 66a73560-8a25-096e-b25d-926bc838734b
 11 9a3cd88c-6b69-430c-9241-c0ea5188a083
 12 f5219523-252a-6615-aefb-b683ebe35a89
 13 66fdff3d-02de-7c21-b6d7-eb6bda54dce3
 14 546562c3-a480-4765-bfe8-ce17608cfa8b
 15 45648e83-4811-2686-9ad4-dee67941a09c
 16 5c90347c-8f9a-346d-9726-ca9ae68a3225
 17 5b5dd706-3e22-0320-84fe-6ac771ff2e5f
 18 2d4007a5-4e15-6ed6-af1c-90b0aafd42e5

Explanation

Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 864007783046742306. Exactly this sequence comes out of new Random(569).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 7 of Run 27 (seed 1,337,299,625): new Random(1337299625), 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 2012-08-15 10:07–10:24).
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