201310020714 1nkqiz

explained decrypted filler

seed 862

Metadata

Post ID: 1nkqiz
Title: 201310020714 → 2013-10-02 07:14 on A858's clock
Posted (UTC): 2013-10-02 11:14:55
Timezone: UTC−4 · title 07:14 against posted 11:14 UTC
Author: [deleted]
Account: A858DE45F56D9BC9 main account
Subreddit: r/A858DE45F56D9BC9 the main subreddit
Category: F3 filler: 3DES(name/title) → GUID list, seed known
Size: 1,296 hex characters · 648 bytes
Cipher: 3DES-EDE2 (two-key Triple DES), ECB, PKCS7
Key: MD5(A858DE45F56D9BC9201310020714) = 1c71b4df02329ecb06bb2d35399b7c85 (name+title)
GUIDs: 20
Filler GUID seed: new Random(862).Next(9) ✓ verified
Run: Run 53 (seed 26,950,390) (seed)
Draw: 149 · predicted N = 20 ✓
Machine boot: 2013-09-12 09:30–10:30 (seed = uptime at app start)
Sources: community-archive, arctic-shift · body from community-archive
Links: Reddit · Arctic Shift · JSON
Score · comments: 6 · 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: 1,296 hex characters = 648 bytes = 81 8-byte 3DES blocks.
Derive the key. Password = A858DE45F56D9BC9201310020714 (name+title). Key = MD5(password) = 1c71b4df02329ecb06bb2d35399b7c85, used as a two-key 3DES key.
Decrypt. 3DES-EDE2 in ECB mode, then strip the PKCS7 padding. The plaintext is 20 GUIDs as hex (shown below).

Decrypted: GUID list

  1 449e6962-5196-05c7-a6af-79f2d071a21a
  2 7bf343be-82a7-6f60-a8ba-2e28177019a1
  3 ffd16886-858f-2c8f-a693-e43850dcc578
  4 d0df306d-0283-4f4e-a7a8-7f491776250d
  5 4bf39603-ed9b-3b80-9d8a-5e064f713a2e
  6 7b7a5c42-9e62-747b-aedc-fb55c21c0c8c
  7 fbe65717-2141-1e27-9a3c-1fc8797c222f
  8 8a28d7c6-7629-8368-b689-c622be68e043
  9 e2ec1bbd-d7a3-5e80-9ab0-f45d24f233a8
 10 a7e86234-7395-19f1-936f-241bb8857802
 11 f7f2f84d-a7ad-333e-981d-d57200104e2e
 12 4a2d3ec7-f512-3781-8dc5-ebc4df46ebe0
 13 a55fcba3-4587-18aa-b61b-20c6c0db4304
 14 48d3a0b6-13a0-8e03-887c-d25475f0523d
 15 fd9de87a-a43f-3450-b139-57cfdfcac1d7
 16 324da6e1-3c19-31ad-b81b-a1545ea6b938
 17 e8dd9cc8-30c7-1882-82ca-545855505251
 18 541c8624-e8f1-3304-bf02-3762a494eafe
 19 32d72fe6-ace8-09fc-8bfa-fe2c677b64a9
 20 6ed69eee-4e39-0531-8e4a-497181a44b1f

Explanation

Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 06243718513318331300. Exactly this sequence comes out of new Random(862).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.
Explain the count. This post is draw 149 of Run 53 (seed 26,950,390): new Random(26950390), 4·Next(1,12) per post. The RNG predicts N = 20; the post has N = 20 ✓. The seed is the machine's uptime in ms when the app started (boot 2013-09-12 09:30–10:30).
Conclusion. Filler. The content is fully explained by the two RNGs.

Metadata

From the post to its content

As posted (encrypted)

Decrypted: GUID list

Explanation

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