201309092159 1m1p3g

explained decrypted filler

seed 572

Metadata

Post ID: 1m1p3g
Title: 201309092159 → 2013-09-09 21:59 on A858's clock
Posted (UTC): 2013-09-09 17:59:49
Timezone: UTC+4 · title 21:59 against posted 17:59 UTC
Author: [deleted]
Account: A858DE45F56D9BC9 main account
Subreddit: r/A858DE45F56D9BC9 the main subreddit
Category: F3 filler: 3DES(name/title) → GUID list, seed known
Size: 1,296 hex characters · 648 bytes
Cipher: 3DES-EDE2 (two-key Triple DES), ECB, PKCS7
Key: MD5(A858DE45F56D9BC9201309092159) = 82cf19396b19ff400c52bd1230eff406 (name+title)
GUIDs: 20
Filler GUID seed: new Random(572).Next(9) ✓ verified
Run: Run 52 (seed 1,430,705,843) (seed)
Draw: 79 · predicted N = 20 ✓
Machine boot: 2013-08-14 07:34–10:34 (seed = uptime at app start)
Sources: community-archive, arctic-shift · body from community-archive
Links: Reddit · Arctic Shift · JSON
Score · comments: 2 · 0
Tags: automated (decryptable)2013Encrypted masked GUID listkey: name+titlerun: seed

From the post to its content

As posted (encrypted)

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

Read the ciphertext. Strip whitespace: 1,296 hex characters = 648 bytes = 81 8-byte 3DES blocks.
Derive the key. Password = A858DE45F56D9BC9201309092159 (name+title). Key = MD5(password) = 82cf19396b19ff400c52bd1230eff406, used as a two-key 3DES key.
Decrypt. 3DES-EDE2 in ECB mode, then strip the PKCS7 padding. The plaintext is 20 GUIDs as hex (shown below).

Decrypted: GUID list

  1 94b18b10-21ed-4bdd-b507-5c8ddd278b90
  2 a7761a73-9ec5-5397-b5bc-f54f0d11bab7
  3 8e851ce5-e150-5e8c-a1f3-6ffedd3993aa
  4 97244c4c-43ff-56b2-b921-5318de4a1151
  5 08fabd2f-829c-4564-be7e-42801c556d07
  6 483eb5fc-2b10-3f52-8d2e-719a9f3bebf6
  7 99cf4beb-8bb6-19a6-944a-96582201c8a4
  8 3e5c2961-d005-3559-b78e-320e610fbb0b
  9 22b76e2d-2e5f-65c3-a085-e20653549769
 10 9adc6390-5041-166c-b698-35bb11cbaa46
 11 c2ed398d-d0ac-6036-b414-28c0abc3f65f
 12 4eb118a3-85be-03e8-b9f1-f5ba3ad5d4b4
 13 014083a9-acb4-7f8d-afcc-bfbbb8ede429
 14 7859ce0b-8192-0e28-af6a-f9b1f24cf664
 15 c8ca98dd-0fb3-38e9-a5a3-a93f2cd6fa58
 16 f32b7191-f2c3-2ebb-b177-05c021f366fa
 17 1c3e5197-b61f-225e-aa88-53170a390f63
 18 8ce5603d-b951-5a13-8529-005a1df102a5
 19 f5896ae5-1613-1712-af73-82eda5cbdf62
 20 67f7fb26-d33f-7862-8ff0-eeaaa58b1a4c

Explanation

Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 45554313616070322517. Exactly this sequence comes out of new Random(572).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 79 of Run 52 (seed 1,430,705,843): new Random(1430705843), 4·Next(1,12) per post. The RNG predicts N = 20; the post has N = 20 ✓. The seed is the machine's uptime in ms when the app started (boot 2013-08-14 07:34–10:34).
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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