A858DE45F56D9BC9 archive

201304050645 1bopkq

explained decrypted filler

seed 764

Metadata

Post ID
1bopkq
Title
201304050645 → 2013-04-05 06:45 on A858's clock
Posted (UTC)
2013-04-04 20:45:58
Timezone
UTC+10 · title 06:45 against posted 20:45 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(A858DE45F56D9BC9201304050645) = 7df661d97f232ede3debce7c294f3920 (name+title)
GUIDs
32
Filler GUID seed
new Random(764).Next(9) ✓ verified
Run
Run 44 (seed 1,087,967,875) (seed)
Draw
63 · 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
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: 2,064 hex characters = 1,032 bytes = 129 8-byte 3DES blocks.
  • Derive the key. Password = A858DE45F56D9BC9201304050645 (name+title). Key = MD5(password) = 7df661d97f232ede3debce7c294f3920, 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 53ba6c87-bd14-7c89-8a3c-09e5b43156c1
  2 e2ba5432-1b00-87f6-84d2-7e61affd50ec
  3 f4cf7556-8bc1-7809-9e48-2c3d93b5879f
  4 fe15a94b-4ea7-5983-9f01-0db72975b865
  5 181497ff-2c9e-151f-a433-b42437c5e90f
  6 8ca42d78-94cd-105a-90ab-3a13089adad3
  7 6d520231-71c4-1107-b96a-17ec092e8016
  8 746371c6-d3b7-644c-8fd2-bb63ae842464
  9 57870a1d-7e04-4166-881e-a6350116427d
 10 739aedf3-c69c-88ed-b924-4802ae632b02
 11 3000e537-0547-122f-af04-76c9fbb4c449
 12 199e3665-12e5-855d-ad32-f283743ff502
 13 2e9b1736-d4e9-7d96-83ae-616c362720eb
 14 49bd9f8d-8ea4-882b-9bd6-80b706928056
 15 1554b3f0-1e83-6b4c-8dbe-6eb96b5f82f7
 16 b9993ade-151b-1061-b11c-c9fd8e1751a2
 17 40aa9e05-c1dd-058b-a3e6-ebffc8b25168
 18 e4f298a7-ef65-624f-9cc5-c8b6790a2f02
 19 f8fa4c94-51bd-39fa-9b39-11f6765c239d
 20 78ad28a4-ff96-1243-b2ca-1cc629ae3d1d
 21 798cd76e-c493-258a-b484-42e6fe57f02d
 22 ad616521-3453-20ed-91e5-a6397410d141
 23 112a1812-f7a8-1d63-8e0e-03f94e378d9d
 24 49dc51f6-db7a-8310-9dec-04c561de9e8f
 25 b4ad1a0b-280e-564f-ac56-fcbba0557bbb
 26 9ab54e75-0856-8440-803b-4ad558b91d9f
 27 94c863ad-c0a3-7049-98a6-974788157464
 28 974a112f-7b5f-0e6e-b388-0121f50503ac
 29 aeee4d22-d1fc-5ac9-ad06-28992552d0ab
 30 5063f0be-7d01-39a7-a01d-11a0aafc1d30
 31 3a5ec453-6a57-20e7-9514-7a5c5c888fa9
 32 b01f3cb4-edc4-6da4-a7f2-37e4559818ab

Explanation

  1. Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 78751116481878610631221858705326. Exactly this sequence comes out of new Random(764).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 63 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