201210032001 10wlww

explained decrypted filler

3DES(name+title) ECB, 8 GUIDs, seed 753

Metadata

Post ID: 10wlww
Title: 201210032001 → 2012-10-03 20:01 on A858's clock
Posted (UTC): 2012-10-04 00:01:38
Timezone: UTC−4 · title 20:01 against posted 00:01 UTC
Author: [deleted]
Account: A858DE45F56D9BC9 main account
Subreddit: r/A858DE45F56D9BC9 the main subreddit
Category: F3 filler: 3DES(name/title) → GUID list, seed known
Size: 528 hex characters · 264 bytes
Cipher: 3DES-EDE2 (two-key Triple DES), ECB, PKCS7
Key: MD5(A858DE45F56D9BC9201210032001) = eb4d417d599efde1fcf735f77301a28a (name+title)
New here: Missing from the community archive; decrypted here for the first time. (new results)
GUIDs: 8
Filler GUID seed: new Random(753).Next(9) ✓ verified
Run: Run 35 (seed 854,622,578) (seed)
Draw: 120 · predicted N = 8 ✓
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: 8 · 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: 528 hex characters = 264 bytes = 33 8-byte 3DES blocks.
Derive the key. Password = A858DE45F56D9BC9201210032001 (name+title). Key = MD5(password) = eb4d417d599efde1fcf735f77301a28a, used as a two-key 3DES key.
Decrypt. 3DES-EDE2 in ECB mode, then strip the PKCS7 padding. The plaintext is 8 GUIDs as hex (shown below).

Decrypted: GUID list

  1 aef3c350-749c-19aa-9c86-415ff72dc170
  2 6d49bbec-125f-68b1-b344-b7d97fc24169
  3 1db9cd73-9c5c-0988-8004-a8bc1ac34985
  4 a1ac72eb-7baf-2445-b891-516ba2c868a1
  5 9f42947d-dafc-1446-acd9-9db62105fe19
  6 02018957-b304-5c83-8a29-a370a92422b9
  7 2bc87ea4-e083-2f51-b01b-003af95e8e00
  8 9940ee55-0527-100f-9e03-186829cf64f0

Explanation

Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 16021521. Exactly this sequence comes out of new Random(753).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 120 of Run 35 (seed 854,622,578): new Random(854622578), Next(8,64) per post. The RNG predicts N = 8; the post has N = 8 ✓. 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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