201206261228 vn7qi

explained decrypted filler

3DES(name) ECB, 22 GUIDs, seed 340

Metadata

Post ID: vn7qi
Title: 201206261228 → 2012-06-26 12:28 on A858's clock
Posted (UTC): 2012-06-26 19:26:33
Timezone: UTC−7 · title 12:28 against posted 19:26 UTC
Author: [deleted]
Account: A858DE45F56D9BC9 main account
Subreddit: r/A858DE45F56D9BC9 the main subreddit
Category: F3 filler: 3DES(name/title) → GUID list, seed known
Size: 1,424 hex characters · 712 bytes
Cipher: 3DES-EDE2 (two-key Triple DES), ECB, PKCS7
Key: MD5(A858DE45F56D9BC9) = 34a14a42e98ff96095af56604e290cae (name)
New here: Missing from the community archive; decrypted here for the first time. (new results)
GUIDs: 22
Filler GUID seed: new Random(340).Next(9) ✓ verified
Run: Run 3 (seed 1,063,142,882) (seed)
Draw: 73 · predicted N = 22 ✓
Machine boot: 2012-06-14 10:25–10:26 (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: namerun: seed

From the post to its content

As posted (encrypted)

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

Read the ciphertext. Strip whitespace: 1,424 hex characters = 712 bytes = 89 8-byte 3DES blocks.
Derive the key. Password = A858DE45F56D9BC9 (name). Key = MD5(password) = 34a14a42e98ff96095af56604e290cae, used as a two-key 3DES key.
Decrypt. 3DES-EDE2 in ECB mode, then strip the PKCS7 padding. The plaintext is 22 GUIDs as hex (shown below).

Decrypted: GUID list

  1 93fd070c-8d02-3f52-ad9a-91812d15751c
  2 e213e2f1-4a11-59f8-b017-07cea79f5c7a
  3 823036c3-fdd4-354d-95ac-27e39629b113
  4 319c5941-1ea9-1abc-a513-0338f5b68ae6
  5 e2c6a511-b95b-6729-8120-82926a3c6715
  6 026d6c7c-bea8-62c3-aa3e-c47e2ea7cef6
  7 f182a810-54b2-286c-bebc-d231db2ccbd2
  8 a6d90350-9628-0d41-ae61-6281fa8152ba
  9 45ba5652-d567-05b8-9c83-c2d53dafb110
 10 1c4f194e-379d-588f-b129-c5260a0a93d6
 11 8ec69b5a-2c04-7247-823e-fc83b97ba0da
 12 9e2dcf40-1427-8cf9-a569-4c1417cb35f5
 13 8860c6a9-f765-3ae9-af23-14e149c35ffd
 14 7ad76109-7e2e-30d7-b449-50aea8321e5d
 15 e01897d0-15da-8779-92ac-22b3a2b3a80a
 16 ad4319d3-7df7-3dd5-8859-c7cc9d282de9
 17 502919a1-e75d-7f11-93f5-1742c9c6084a
 18 de3cba2c-e800-7a34-9aca-f6d7c270e12f
 19 67f427fa-3a7b-7055-89dc-f4c93a411d26
 20 f96584eb-b367-87ee-a1d4-984c99975e1a
 21 c01abd8b-54f9-8dea-baa9-5a233510410f
 22 b7858ad9-0359-2322-ac26-717e0d40b556

Explanation

Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 3531662005783383777882. Exactly this sequence comes out of new Random(340).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 73 of Run 3 (seed 1,063,142,882): new Random(1063142882), Next(8,24) per post. The RNG predicts N = 22; the post has N = 22 ✓. The seed is the machine's uptime in ms when the app started (boot 2012-06-14 10:25–10:26).
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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