A858DE45F56D9BC9 archive

201208120050 y2xuq

explained decrypted filler

seed 251

Metadata

Post ID
y2xuq
Title
201208120050 → 2012-08-12 00:50 on A858's clock
Posted (UTC)
2012-08-12 04:47:52
Timezone
UTC−4 · title 00:50 against posted 04:47 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(A858DE45F56D9BC9A858DE45F56D9BC9) = 0dcc4bd9e114ebc42078977dc9125404 (name+name)
GUIDs
31
Filler GUID seed
new Random(251).Next(9) ✓ verified
Run
Run 22 (seed 528,385,484) (seed)
Draw
73 · predicted N = 31 ✓
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
7 · 0
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: 2,000 hex characters = 1,000 bytes = 125 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 31 GUIDs as hex (shown below).

Decrypted: GUID list

  1 92463e41-d0f7-72b6-9853-979ef6d4425e
  2 a85afcef-426c-4721-88a4-3aca547be399
  3 8c2301e5-5888-13d1-a19e-e94f0bd0a104
  4 7a709977-f445-1db5-8977-023dd64e79fb
  5 6c4a2e9a-2100-4a41-9472-bd997899f257
  6 883639e5-befb-8e0b-befd-be3ded669651
  7 87187c9c-06e0-311a-a63f-5bc0fc0d9ba2
  8 7745d4a9-0ff2-3433-be86-cedc51976f8d
  9 4a5d2ed4-7e29-0a28-92e8-63f214bc1854
 10 d33817c5-7259-7693-9990-e9d8158897ba
 11 28173840-770f-1a87-8d30-3a620e760b27
 12 2140b4b0-2a6a-3789-8df9-c407a7912e0a
 13 e2b44252-c706-1375-9f5f-2fdb85f14797
 14 ac97db5e-7d1f-0420-a59d-e663736f3d02
 15 39083cf8-6404-6d98-9b51-520bbb132e90
 16 134d329f-af0b-7f1b-bc70-aefcea612fdd
 17 16f4e0ca-1d61-31b0-98c9-a991c7df063f
 18 07fd06df-dd23-5b0d-b930-ddb839d232f6
 19 6a007675-85fe-4e38-8c54-1edf08e82095
 20 299aad71-7fb8-4adf-9015-c8521c4f6293
 21 5a76b302-6d0c-10b6-b04f-b836f62d3997
 22 9c6813cc-3324-31d9-b1c6-1745036450e6
 23 47282b36-a99b-3301-a7a6-23e3aa21250e
 24 cad867c3-43ce-6188-8d60-a70a396d4dbd
 25 cb1e87e1-b3fb-2c97-a278-c9d372625f94
 26 c746fdda-a802-898f-a4c6-fe0ce307e0d5
 27 57f38fe0-9053-67e4-943d-9143a19a4334
 28 8554f9a3-9777-12b5-a91a-c98983fed3b9
 29 4678c4e8-fa71-7041-830c-600358c42948
 30 50367300-eb12-29f0-99e8-cdcb984df0c8
 31 b0e7ff81-28e8-732f-8e2c-a3d8eb9f10f8

Explanation

  1. Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 7411483307131067354413362861727. Exactly this sequence comes out of new Random(251).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 73 of Run 22 (seed 528,385,484): new Random(528385484), 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 2012-07-27 19:02–19:13).
  3. Conclusion. Filler. The content is fully explained by the two RNGs.

Related

Findings: Mask digit · Count RNG & runs