A858DE45F56D9BC9 archive

201208120010 y2vwx

explained decrypted filler

seed 751

Metadata

Post ID
y2vwx
Title
201208120010 → 2012-08-12 00:10 on A858's clock
Posted (UTC)
2012-08-12 04:07:49
Timezone
UTC−4 · title 00:10 against posted 04:07 UTC
Author
[deleted]
Account
A858DE45F56D9BC9 main account
Subreddit
r/A858DE45F56D9BC9 the main subreddit
Category
F3 filler: 3DES(name/title) → GUID list, seed known
Size
1,872 hex characters · 936 bytes
Cipher
3DES-EDE2 (two-key Triple DES), ECB, PKCS7
Key
MD5(A858DE45F56D9BC9A858DE45F56D9BC9) = 0dcc4bd9e114ebc42078977dc9125404 (name+name)
GUIDs
29
Filler GUID seed
new Random(751).Next(9) ✓ verified
Run
Run 22 (seed 528,385,484) (seed)
Draw
69 · predicted N = 29 ✓
Machine boot
2012-07-27 19:02–19:13 (seed = uptime at app start)
Sources
community-archive, arctic-shift · body from community-archive
Links
Reddit · Arctic Shift · JSON
Score · comments
30 · 11
Tags
automated (decryptable)2012Encrypted masked GUID listkey: name+namerun: seed

From the post to its content

As posted (encrypted)

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
  • Read the ciphertext. Strip whitespace: 1,872 hex characters = 936 bytes = 117 8-byte 3DES blocks.
  • Derive the key. Password = A858DE45F56D9BC9A858DE45F56D9BC9 (name+name). Key = MD5(password) = 0dcc4bd9e114ebc42078977dc9125404, used as a two-key 3DES key.
  • Decrypt. 3DES-EDE2 in ECB mode, then strip the PKCS7 padding. The plaintext is 29 GUIDs as hex (shown below).

Decrypted: GUID list

  1 a13d9dfa-8a8b-0820-887f-9c661e3fcdbe
  2 48ffc7ac-0da9-1ebd-919b-d07b42d53ef7
  3 34441552-fba7-68d2-836b-b907be7aedd6
  4 129d1b58-4b83-78c9-b130-b221e55ecdfe
  5 470ff2e0-b571-2138-b745-276bad51e87a
  6 92525317-a689-7c35-aa79-f0ea00e8fa56
  7 801c5b80-46c7-3753-8286-38c9c565e65a
  8 dd712352-84a9-15cc-92ed-d99e9584e0e4
  9 1cc63d4e-563d-7682-a04f-dc7f6517bced
 10 36a5c429-0802-1831-910d-607ab2fc8e19
 11 9355597e-67ab-5737-a8dc-a85909734dbe
 12 50855032-4818-76fa-97ce-0201d9112cba
 13 6858a1ce-9e72-8feb-a979-ed06a0bb9d90
 14 70acc33b-2ad7-1b9b-947f-0d8c9d603eeb
 15 6e68b5fb-9950-5ead-ab0a-83318bb81b6a
 16 ca55b796-3291-01d7-9a59-8fe0d5f7b8e0
 17 148dc6af-c030-48e5-aa9a-a60ebbd28936
 18 59765114-ba02-547d-b69f-b36e1b6c38e1
 19 e9f7fba4-a9d2-0d24-9bd6-6b243459d666
 20 815a5ffb-3172-04d5-9eaf-717abb1afb4e
 21 5d4392e0-c8da-5d26-a13f-18b21d6bebd7
 22 22cc02f2-5892-01b7-920c-2f25086bab59
 23 b499f5ef-70f3-8ad0-be0f-e1b71db0ee1f
 24 51233a50-5243-3e36-989d-d7b2e194fb01
 25 e245e84e-500d-28c9-8f00-738bdfca341e
 26 78e320aa-bd85-5e8a-8049-59af1246e6d0
 27 a1d8679a-233a-5f36-9d27-7c1bf5eb56ec
 28 c8610c2c-12e0-0227-a75b-3f697ad857ce
 29 24cd9e3b-7526-819f-a665-d07a9f398e0e

Explanation

  1. Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 01672731715781504500508325508. Exactly this sequence comes out of new Random(751).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 69 of Run 22 (seed 528,385,484): new Random(528385484), Next(8,64) per post. The RNG predicts N = 29; the post has N = 29 ✓. The seed is the machine's uptime in ms when the app started (boot 2012-07-27 19:02–19:13).
  3. Conclusion. Filler. The content is fully explained by the two RNGs.

Related

Findings: Mask digit · Count RNG & runs