A858DE45F56D9BC9 archive

201210120500 11cwu9

explained decrypted filler

seed 436

Metadata

Post ID
11cwu9
Title
201210120500 → 2012-10-12 05:00 on A858's clock
Posted (UTC)
2012-10-12 09:00:09
Timezone
UTC−4 · title 05:00 against posted 09:00 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(A858DE45F56D9BC9201210120500) = 7be8def7407d787ce7fa011c0ff2b897 (name+title)
GUIDs
31
Filler GUID seed
new Random(436).Next(9) ✓ verified
Run
Run 36 (seed 335,015) (seed)
Draw
9 · predicted N = 31 ✓
Machine boot
2012-10-10 20:54–00:54 (seed = uptime at app start)
Sources
community-archive, arctic-shift · body from community-archive
Links
Reddit · Arctic Shift · JSON
Score · comments
13 · 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 = A858DE45F56D9BC9201210120500 (name+title). Key = MD5(password) = 7be8def7407d787ce7fa011c0ff2b897, 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 ca1a27c4-2edc-4474-9e71-6e582e8c30f0
  2 5e38397e-857a-6d53-a166-a66c586bce6d
  3 b340f214-d972-4e27-a89f-a307d4f732ab
  4 a52aa5a6-7efb-5fef-9461-cd9a12e0b7ee
  5 893bd460-6abc-0d13-a92c-6e98422d9e23
  6 2e215d4c-c1e5-5ce6-8df3-ac945fa88197
  7 f23e3e32-ea64-26b3-9615-c12664c6b492
  8 b87e0f0b-0400-122d-a06f-3cba621be087
  9 ec8f51fc-3cf1-82e8-a454-176346b6df91
 10 874aaac8-55fd-0d29-ad27-9e4d6bb405fd
 11 79302b09-b424-47c0-8017-63f41929ca18
 12 328c7502-9f7a-7b81-a9b4-8cad85e4bcd0
 13 48692aa8-58c1-39d1-80b1-b0a0f7d89e22
 14 6412e018-b222-2a43-acd0-2a7fb82b006f
 15 445b2dc3-2f04-1d40-a2bf-5e002c762dd5
 16 ded1582b-f16e-2dba-8680-d5242b4f2296
 17 70a985f1-ac7c-1d9d-a532-a6cea6e1bf9b
 18 84af951b-8cb6-2afb-8dd7-7ddaca7e16ca
 19 e0af6d4a-113a-4d6e-9f59-acd7447d6c19
 20 ff7b1a4c-4c2d-1d3c-8ac5-6b5003421020
 21 740f8496-4871-6c6d-8dc3-4bfe083d4ca6
 22 d01b2777-3e31-7bee-848c-c74ed9d57276
 23 a2bcb84c-fc8c-6a7a-8311-a6a0ffa7034a
 24 23f4325f-4248-3d78-81d7-f6f5f37e2094
 25 3d046787-203b-3d07-935e-c4d1a448d96b
 26 0108e585-ec84-8c6b-918d-f8c862db074c
 27 80e5d558-2e26-71fd-a7c9-dba580936c16
 28 0aa6811b-9333-7c04-a0bc-434bc58ee4fa
 29 7d3cbd89-4651-8d3a-8015-e9e1b25c12ea
 30 fcb37617-03a2-1e13-9ac5-4dd47fc2516a
 31 bc9c0cdc-6405-1a9e-85bf-9a79946f92a6

Explanation

  1. Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 4645052180473212124167633877811. Exactly this sequence comes out of new Random(436).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 9 of Run 36 (seed 335,015): new Random(335015), 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 2012-10-10 20:54–00:54).
  3. Conclusion. Filler. The content is fully explained by the two RNGs.

Related

Findings: Mask digit · Count RNG & runs