A858DE45F56D9BC9 archive

201207071936 w69xd

explained decrypted filler

seed 829

Metadata

Post ID
w69xd
Title
201207071936 → 2012-07-07 19:36 on A858's clock
Posted (UTC)
2012-07-07 10:34:19
Timezone
UTC+9 · title 19:36 against posted 10:34 UTC
Author
[deleted]
Account
A858DE45F56D9BC9 main account
Subreddit
r/A858DE45F56D9BC9 the main subreddit
Category
F3 filler: 3DES(name/title) → GUID list, seed known
Size
1,936 hex characters · 968 bytes
Cipher
3DES-EDE2 (two-key Triple DES), ECB, PKCS7
Key
MD5(A858DE45F56D9BC9) = 34a14a42e98ff96095af56604e290cae (name)
GUIDs
30
Filler GUID seed
new Random(829).Next(9) ✓ verified
Run
Run 11 (seed 37,057,156) (seed)
Draw
35 · predicted N = 30 ✓
Machine boot
2012-07-05 09:16–10:46 (seed = uptime at app start)
Sources
community-archive, arctic-shift · body from community-archive
Links
Reddit · Arctic Shift · JSON
Score · comments
5 · 0
Tags
automated (decryptable)2012Encrypted masked GUID listkey: namerun: seed

From the post to its content

As posted (encrypted)

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
  • Read the ciphertext. Strip whitespace: 1,936 hex characters = 968 bytes = 121 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 30 GUIDs as hex (shown below).

Decrypted: GUID list

  1 41fc03b0-ae90-7711-b6a2-8416aaf891ff
  2 6a686466-5f00-0eb4-b416-cc517e028598
  3 b1a80b6a-0350-2441-8234-697f9802f817
  4 b8322e8f-590f-440c-9bdd-935edebd5b37
  5 a731d7ca-c9e4-44ba-9342-0f34d91c789f
  6 e6e5cc67-0dba-0599-bf0f-3d37c062cddf
  7 47baf63a-d504-3e6f-ba71-3ca1d7b184b8
  8 d4c445a0-0123-3e36-b797-0fce0360abb4
  9 c23e3cb7-c433-4d7a-862b-287117059d33
 10 8a41a5a4-add1-8493-923d-e740aad433ae
 11 fa78e4b9-aaef-0365-a97b-885018c3f94f
 12 a354d6a1-3c16-619b-9532-e5030ea38e84
 13 2c2dff0c-4c80-4dd0-bf42-59ea7760987d
 14 31795eb8-5da7-6d7a-948a-6d32e77d0fa1
 15 11719c51-a57a-2e38-9b63-0868df85bd3e
 16 dbca70b9-c370-6daf-81d5-4d6f47685104
 17 38983a12-ed5e-3566-83df-bb688b5d8d7c
 18 3596efc9-18f1-8573-8923-2f6f3984dc86
 19 d164bb0b-530a-1d56-8ad8-7acf85aa7b4b
 20 081a6513-4e29-2bf0-8eb7-3384dc4c7cc8
 21 80a3d906-cb9f-8224-9594-921e31f3d6f6
 22 9af36701-05de-2619-a79b-aecd69674ecc
 23 405fe3a6-80e5-0544-8c6b-dd746443be3c
 24 004daeb4-1de0-5cb5-976d-a8b51d115e66
 25 88b8401f-2934-8bb6-969b-8fd7b7afd2d3
 26 e23f5b4b-a89a-64a0-bc14-df50e90a3efc
 27 58169e33-fee6-6f64-8388-18ae76e32bd4
 28 bf726d90-c013-34dc-a5cd-e7240bc61297
 29 608d2464-17ad-4830-8f42-16cf07fa78a7
 30 af65ed06-fe7a-6d36-bf43-7693ab3c2b2e

Explanation

  1. Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 702440334806462638128205866346. Exactly this sequence comes out of new Random(829).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 35 of Run 11 (seed 37,057,156): new Random(37057156), Next(8,64) per post. The RNG predicts N = 30; the post has N = 30 ✓. The seed is the machine's uptime in ms when the app started (boot 2012-07-05 09:16–10:46).
  3. Conclusion. Filler. The content is fully explained by the two RNGs.

Related

Findings: Mask digit · Count RNG & runs