A858DE45F56D9BC9 archive

201208170253 yd6s8

explained decrypted filler

seed 576

Metadata

Post ID
yd6s8
Title
201208170253 → 2012-08-17 02:53 on A858's clock
Posted (UTC)
2012-08-17 06:53:27
Timezone
UTC−4 · title 02:53 against posted 06:53 UTC
Author
[deleted]
Account
A858DE45F56D9BC9 main account
Subreddit
r/A858DE45F56D9BC9 the main subreddit
Category
F3 filler: 3DES(name/title) → GUID list, seed known
Size
2,000 hex characters · 1,000 bytes
Cipher
3DES-EDE2 (two-key Triple DES), ECB, PKCS7
Key
MD5(A858DE45F56D9BC9201208170253) = 951678721c17670d71f64455ba834ee6 (name+title)
GUIDs
31
Filler GUID seed
new Random(576).Next(9) ✓ verified
Run
Run 25 (seed 158,297,437) (seed)
Draw
3 · predicted N = 31 ✓
Machine boot
2012-08-15 10:14–10:24 (seed = uptime at app start)
Sources
community-archive, arctic-shift · body from community-archive
Links
Reddit · Arctic Shift · JSON
Score · comments
0 · 0
Tags
automated (decryptable)2012Encrypted masked GUID listkey: name+titlerun: seed

From the post to its content

As posted (encrypted)

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
  • Read the ciphertext. Strip whitespace: 2,000 hex characters = 1,000 bytes = 125 8-byte 3DES blocks.
  • Derive the key. Password = A858DE45F56D9BC9201208170253 (name+title). Key = MD5(password) = 951678721c17670d71f64455ba834ee6, used as a two-key 3DES key.
  • Decrypt. 3DES-EDE2 in ECB mode, then strip the PKCS7 padding. The plaintext is 31 GUIDs as hex (shown below).

Decrypted: GUID list

  1 904da01c-471f-528b-81c9-894b966d5cbe
  2 a6b1693f-e841-7b31-a38d-d3d4b638e69b
  3 77a7d67b-6ccf-3330-99a6-daca94f7d4cc
  4 a6110fd0-1668-400b-a2c2-2a91b6a378f9
  5 9f0f23c4-d97f-29c1-917b-2ad7770f2d70
  6 4d949881-cd27-8a45-9b3e-9827566e44c6
  7 a625c305-7f83-8c74-a61f-04f0e1d89103
  8 8783e13a-1bc6-33e7-91ff-5bbd2e244762
  9 ec753f08-0ea4-2eac-ae7f-3a89f752fd54
 10 a10492d9-b3a7-60c4-a5fa-e5aa6d65ebca
 11 eeb3a161-677f-5341-8ff9-c654452a1d99
 12 de4854e9-b597-18ed-a642-60e85366ecd9
 13 4f65834f-c207-5dfa-9bbd-e949c703b428
 14 f188fc50-cb72-19ff-8c94-afe0afe10211
 15 7286c677-c1ad-1201-916e-0ef03f3c6f53
 16 9cf427e9-9c9a-66c7-a567-c21a85e12eed
 17 fd9c7f17-aa4e-8182-b34f-c1dede85c1bf
 18 e13790c9-c2b1-1b17-9d30-9f3bab4b5a83
 19 1d5dbd50-292c-2b77-b24a-c5199fd6639a
 20 72b0f179-54d7-315b-8e79-1cbfb7fb1f5f
 21 d865900b-5983-3a52-920e-45df20d80315
 22 83072e43-f453-19a3-a018-a0be5841d9e0
 23 832afe7f-6fc1-303d-8c3b-3959b75ab895
 24 b7f8c5e3-d459-2816-ab24-c6397414e263
 25 47f86633-a3e5-1664-92b0-a632803ec253
 26 3a08a9ba-5851-86bc-ad82-45f460564983
 27 b4e9e4d7-8ccb-1609-a963-25e3fd578a5a
 28 fa64cbc9-1c56-518c-b259-d8a33ec73374
 29 08870621-e1bb-5f06-ae80-7922133b0235
 30 dd4a4e1e-3b5b-826f-b140-b725587db344
 31 0f0db003-6cef-786b-9357-a51b73d619b2

Explanation

  1. Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 5734288326515116812331321815587. Exactly this sequence comes out of new Random(576).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 3 of Run 25 (seed 158,297,437): new Random(158297437), Next(8,64) per post. The RNG predicts N = 31; the post has N = 31 ✓. The seed is the machine's uptime in ms when the app started (boot 2012-08-15 10:14–10:24).
  3. Conclusion. Filler. The content is fully explained by the two RNGs.

Related

Findings: Mask digit · Count RNG & runs