201210042222 10z0jc

explained decrypted filler

3DES(name+title) ECB, 13 GUIDs, seed 99

Metadata

Post ID: 10z0jc
Title: 201210042222 → 2012-10-04 22:22 on A858's clock
Posted (UTC): 2012-10-05 02:22:48
Timezone: UTC−4 · title 22:22 against posted 02:22 UTC
Author: [deleted]
Account: A858DE45F56D9BC9 main account
Subreddit: r/A858DE45F56D9BC9 the main subreddit
Category: F3 filler: 3DES(name/title) → GUID list, seed known
Size: 848 hex characters · 424 bytes
Cipher: 3DES-EDE2 (two-key Triple DES), ECB, PKCS7
Key: MD5(A858DE45F56D9BC9201210042222) = 4d2d5aa957c049cb70af0a49e5fcb9bb (name+title)
New here: Missing from the community archive; decrypted here for the first time. (new results)
GUIDs: 13
Filler GUID seed: new Random(99).Next(9) ✓ verified
Run: Run 35 (seed 854,622,578) (seed)
Draw: 199 · predicted N = 13 ✓
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: 1 · 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: 848 hex characters = 424 bytes = 53 8-byte 3DES blocks.
Derive the key. Password = A858DE45F56D9BC9201210042222 (name+title). Key = MD5(password) = 4d2d5aa957c049cb70af0a49e5fcb9bb, used as a two-key 3DES key.
Decrypt. 3DES-EDE2 in ECB mode, then strip the PKCS7 padding. The plaintext is 13 GUIDs as hex (shown below).

Decrypted: GUID list

  1 2e436067-0db0-48b3-b326-d1cca56fbc64
  2 02cd2896-662c-7268-a8c0-fe65705187dc
  3 3ce7e3a4-dca3-8698-b9e7-55b322a33931
  4 aff3710a-a7c8-67c8-993d-9c0c34848ab8
  5 18de053a-7714-8979-8236-61cce22c9e51
  6 9c20450d-0af9-009a-bc60-c6c3d26f5e2a
  7 1668e060-06b1-27f2-b8e4-b1db64a66c14
  8 6a2df452-84fd-0005-82a2-07e58230f9bd
  9 118f617b-8b00-2c85-9dd5-7638a7248b0e
 10 c0c17ef5-a8d5-7d9d-bebe-73f5e1ee03f9
 11 85a65738-af76-2b04-8d1b-2cc7bc81b8c4
 12 8b5a2c7d-fba9-6c97-879f-ed09e291ca3f
 13 6263b1fd-2c2f-60bb-bd8a-31b17973f92c

Explanation

Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 4786802027266. Exactly this sequence comes out of new Random(99).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 199 of Run 35 (seed 854,622,578): new Random(854622578), Next(8,64) per post. The RNG predicts N = 13; the post has N = 13 ✓. 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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