A858DE45F56D9BC9 archive

201304041521 1bn6ug

explained decrypted filler

seed 540

Metadata

Post ID
1bn6ug
Title
201304041521 → 2013-04-04 15:21 on A858's clock
Posted (UTC)
2013-04-04 05:21:59
Timezone
UTC+10 · title 15:21 against posted 05:21 UTC
Author
[deleted]
Account
A858DE45F56D9BC9 main account
Subreddit
r/A858DE45F56D9BC9 the main subreddit
Category
F3 filler: 3DES(name/title) → GUID list, seed known
Size
2,064 hex characters · 1,032 bytes
Cipher
3DES-EDE2 (two-key Triple DES), ECB, PKCS7
Key
MD5(A858DE45F56D9BC9201304041521) = 2bf3f3ada6becefc4ffaf90e957c348b (name+title)
GUIDs
32
Filler GUID seed
new Random(540).Next(9) ✓ verified
Run
Run 44 (seed 1,087,967,875) (seed)
Draw
42 · predicted N = 32 ✓
Machine boot
2013-03-21 09:35–10:19 (seed = uptime at app start)
Sources
community-archive, arctic-shift · body from community-archive
Links
Reddit · Arctic Shift · JSON
Score · comments
1 · 1
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: 2,064 hex characters = 1,032 bytes = 129 8-byte 3DES blocks.
  • Derive the key. Password = A858DE45F56D9BC9201304041521 (name+title). Key = MD5(password) = 2bf3f3ada6becefc4ffaf90e957c348b, used as a two-key 3DES key.
  • Decrypt. 3DES-EDE2 in ECB mode, then strip the PKCS7 padding. The plaintext is 32 GUIDs as hex (shown below).

Decrypted: GUID list

  1 a631e9b2-10e4-767d-9e44-036cec22a6bc
  2 b777fd58-a1f3-2f45-b924-c2fb9d321e09
  3 404ccadb-d4cd-1b5c-8fa7-5e353b7f686a
  4 68d89006-cac3-736b-8080-5e66bb6bc633
  5 20b3a5f4-6aac-047b-b65b-d0099b79df9d
  6 2216fe3d-bd86-4a31-92ef-a66e88d39842
  7 4dae4267-d409-7c31-8c9b-33745fa43d2d
  8 7df5f61f-fb8b-3cb1-a134-4c38c04afb52
  9 04db826a-ebad-7f71-96da-9e9d5c23c5b8
 10 07fbbdd1-b8ee-3745-997e-4a03968582e7
 11 958d7e37-8d61-1c2c-bbe3-7e9d32c305f3
 12 7db620e5-362d-0dea-af52-fab68d6418d2
 13 f833fee4-3d54-7681-a468-c65478187d5c
 14 963b1f27-4c0c-3e70-8da9-82564abe3ad6
 15 c53fbd0d-0c52-8bc0-a3a9-a43e456d97f9
 16 539370d2-98cc-2c05-add0-ca76781a94fa
 17 c88e2a1c-03d2-751b-bc24-02f73477bba1
 18 8779adcd-3f59-7f78-8d37-a4f9c5f0f97c
 19 bff05ec5-c323-25d4-8306-7a8e2c17c8f6
 20 73b65fc9-ec6b-3510-90d7-87ac7f057c64
 21 911ea1db-2f2e-54d9-b045-61901a3800b2
 22 3e9f3f85-724e-2888-9754-893ebade12e2
 23 9c0dccbd-7304-2e77-b07c-aa18679abc66
 24 fad4da02-edb7-650b-a148-c9adb2cbf351
 25 2e748447-27c9-50fb-80df-08ca7fc09930
 26 b2d8459d-98db-7cd3-abce-76881a0dd1be
 27 17d90126-7e05-1558-88f1-46681a0f1a49
 28 5a0fc3b5-0282-2b58-b92e-ad7c4e0aab17
 29 3c37c79c-3b4b-6b2c-8913-427369c26fc7
 30 226f0af6-6fbd-8ef2-af3b-fcdf5260b284
 31 1af9770f-b895-40d3-b068-04ca26407833
 32 e53ae3ee-ca0a-69fc-a897-3477f5d5f56f

Explanation

  1. Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 72170473731073827723522657126846. Exactly this sequence comes out of new Random(540).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.
  2. Explain the count. This post is draw 42 of Run 44 (seed 1,087,967,875): new Random(1087967875), 4·Next(8,16) per post. The RNG predicts N = 32; the post has N = 32 ✓. The seed is the machine's uptime in ms when the app started (boot 2013-03-21 09:35–10:19).
  3. Conclusion. Filler. The content is fully explained by the two RNGs.

Related

Findings: Mask digit · Count RNG & runs