201210050202 10zbwk

explained decrypted filler

3DES(name+title) ECB, 14 GUIDs, seed 611

Metadata

Post ID: 10zbwk
Title: 201210050202 → 2012-10-05 02:02 on A858's clock
Posted (UTC): 2012-10-05 06:02:56
Timezone: UTC−4 · title 02:02 against posted 06:02 UTC
Author: [deleted]
Account: A858DE45F56D9BC9 main account
Subreddit: r/A858DE45F56D9BC9 the main subreddit
Category: F3 filler: 3DES(name/title) → GUID list, seed known
Size: 912 hex characters · 456 bytes
Cipher: 3DES-EDE2 (two-key Triple DES), ECB, PKCS7
Key: MD5(A858DE45F56D9BC9201210050202) = f5de1d661586855d12d7931c0ff396c9 (name+title)
New here: Missing from the community archive; decrypted here for the first time. (new results)
GUIDs: 14
Filler GUID seed: new Random(611).Next(9) ✓ verified
Run: Run 35 (seed 854,622,578) (seed)
Draw: 210 · predicted N = 14 ✓
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: 2 · 2
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: 912 hex characters = 456 bytes = 57 8-byte 3DES blocks.
Derive the key. Password = A858DE45F56D9BC9201210050202 (name+title). Key = MD5(password) = f5de1d661586855d12d7931c0ff396c9, used as a two-key 3DES key.
Decrypt. 3DES-EDE2 in ECB mode, then strip the PKCS7 padding. The plaintext is 14 GUIDs as hex (shown below).

Decrypted: GUID list

  1 4cc10e45-c279-8185-89e7-782ac0aafc8e
  2 488191f8-0aae-0197-95d6-8f3d69108a13
  3 b0909702-6a60-7cc2-97a9-45985e065fd2
  4 bba886f6-e6d2-85cd-b8a9-c9b32a7b78d3
  5 92e4fa85-dc2a-006a-9567-bcb36e492111
  6 7ebaf81c-8c75-4932-89f2-f5d7d13867e1
  7 8fcd7ae1-0343-670e-a2ec-a13af2cdbd33
  8 428f3f16-9099-85e9-be38-86ea2880324a
  9 35a18f9b-f129-5437-9acd-5c7af41753c7
 10 820c701d-065c-5478-bd75-fd746c3c0ec8
 11 c228dfbf-ae19-3b61-a1e5-48fe89beeed2
 12 165841bc-96da-4228-8035-644878f718ec
 13 13ae0b8a-6dac-5ea0-91ac-20f902d7f1ad
 14 7a3b7e8d-a623-3383-87c3-e0609e8bb223

Explanation

Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 80780468553453. Exactly this sequence comes out of new Random(611).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 210 of Run 35 (seed 854,622,578): new Random(854622578), Next(8,64) per post. The RNG predicts N = 14; the post has N = 14 ✓. 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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