201210032021 10wn8o

explained decrypted filler

3DES(name+title) ECB, 18 GUIDs, seed 697

Metadata

Post ID: 10wn8o
Title: 201210032021 → 2012-10-03 20:21 on A858's clock
Posted (UTC): 2012-10-04 00:21:39
Timezone: UTC−4 · title 20:21 against posted 00:21 UTC
Author: [deleted]
Account: A858DE45F56D9BC9 main account
Subreddit: r/A858DE45F56D9BC9 the main subreddit
Category: F3 filler: 3DES(name/title) → GUID list, seed known
Size: 1,168 hex characters · 584 bytes
Cipher: 3DES-EDE2 (two-key Triple DES), ECB, PKCS7
Key: MD5(A858DE45F56D9BC9201210032021) = 4b38bbc34b62635f3664937c777bdbfa (name+title)
New here: Missing from the community archive; decrypted here for the first time. (new results)
GUIDs: 18
Filler GUID seed: new Random(697).Next(9) ✓ verified
Run: Run 35 (seed 854,622,578) (seed)
Draw: 121 · predicted N = 18 ✓
Machine boot: 2012-09-22 10:16–10:36 (seed = uptime at app start)
Sources: arctic-shift · body from arctic-shift
Links: Reddit · Arctic Shift · JSON
Score · comments: 7 · 0
Tags: automated (decryptable)2012Encrypted masked GUID listarctic-onlykey: name+titlerun: seed

From the post to its content

As posted (encrypted)

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

Read the ciphertext. Strip whitespace: 1,168 hex characters = 584 bytes = 73 8-byte 3DES blocks.
Derive the key. Password = A858DE45F56D9BC9201210032021 (name+title). Key = MD5(password) = 4b38bbc34b62635f3664937c777bdbfa, used as a two-key 3DES key.
Decrypt. 3DES-EDE2 in ECB mode, then strip the PKCS7 padding. The plaintext is 18 GUIDs as hex (shown below).

Decrypted: GUID list

  1 5dfadeee-7255-73ba-9e18-20e1fef1b4ee
  2 e4ddaae1-f593-2923-9db5-26e8bd1576be
  3 e93e9808-7df9-8356-b6d6-b4533a9b8dcf
  4 918d9516-ed86-21c9-bd81-dea5b6928c5c
  5 43d9f462-7faf-82da-a3b5-fd22d568aa91
  6 1b9469cb-b1cc-5a7e-b1a7-1c6f01bfd619
  7 4d1829dc-f99a-1df2-827d-92683db2f46c
  8 7ddc5963-ca27-1fed-9d15-d08bf5335bfb
  9 4ff3e30b-4e96-17cb-8221-86f8ca52a740
 10 3831f474-859a-2573-a596-9a371ec7ba22
 11 8b2f8f87-9780-7f53-9a7e-887e87a12714
 12 3b7640e6-6236-56ad-a59a-e6db03c81288
 13 ab336ccd-0ad7-7c30-8002-405e284d160c
 14 80fe7a43-6df5-0887-8fb9-1380e928dde7
 15 ba8bba1e-e1da-7a5e-8518-5e59f752d527
 16 ee768cec-2d49-289c-8a67-bb7aeea725d2
 17 441acfb6-aed5-7fce-903b-036a870b2576
 18 1d9d438d-e22d-1116-8cce-bdf3a01ceef9

Explanation

Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 728285111275707271. Exactly this sequence comes out of new Random(697).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 121 of Run 35 (seed 854,622,578): new Random(854622578), Next(8,64) per post. The RNG predicts N = 18; the post has N = 18 ✓. The seed is the machine's uptime in ms when the app started (boot 2012-09-22 10:16–10:36).
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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