201206260834 vmso6

explained decrypted filler

3DES(name) ECB, 17 GUIDs, seed 246

Metadata

Post ID: vmso6
Title: 201206260834 → 2012-06-26 08:34 on A858's clock
Posted (UTC): 2012-06-26 15:32:53
Timezone: UTC−7 · title 08:34 against posted 15:32 UTC
Author: [deleted]
Account: A858DE45F56D9BC9 main account
Subreddit: r/A858DE45F56D9BC9 the main subreddit
Category: F3 filler: 3DES(name/title) → GUID list, seed known
Size: 1,104 hex characters · 552 bytes
Cipher: 3DES-EDE2 (two-key Triple DES), ECB, PKCS7
Key: MD5(A858DE45F56D9BC9) = 34a14a42e98ff96095af56604e290cae (name)
New here: Missing from the community archive; decrypted here for the first time. (new results)
GUIDs: 17
Filler GUID seed: new Random(246).Next(9) ✓ verified
Run: Run 2 (seed 1,054,905,639) (seed)
Draw: 0 · predicted N = 17 ✓
Machine boot: 2012-06-14 10:26–10:31 (seed = uptime at app start)
Sources: arctic-shift · body from arctic-shift
Links: Reddit · Arctic Shift · JSON
Score · comments: 2 · 0
Tags: automated (decryptable)2012Encrypted masked GUID listarctic-onlykey: namerun: seed

From the post to its content

As posted (encrypted)

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

Read the ciphertext. Strip whitespace: 1,104 hex characters = 552 bytes = 69 8-byte 3DES blocks.
Derive the key. Password = A858DE45F56D9BC9 (name). Key = MD5(password) = 34a14a42e98ff96095af56604e290cae, used as a two-key 3DES key.
Decrypt. 3DES-EDE2 in ECB mode, then strip the PKCS7 padding. The plaintext is 17 GUIDs as hex (shown below).

Decrypted: GUID list

  1 5f2e04f3-d996-26da-bc79-0727f879a5d2
  2 8a729250-ed58-8830-8e8c-c7b2cb3932f0
  3 06ec293c-3a81-6d4f-bbba-48bff81b7d63
  4 1baaca38-0f55-0096-a1e3-bc2c5572c5e5
  5 54566c8c-b081-2f60-94c5-568214544794
  6 96d2600d-4e3b-450f-b12d-22bb6be37595
  7 d0c0ab54-ba6d-1f7c-b85e-7cde5f74a789
  8 8b2a27d4-9f5a-7e51-a462-4d676067379c
  9 48193a27-2576-38fe-9033-0274e310109f
 10 d241dae5-d515-8f44-b764-3d596ffaab70
 11 0794179e-fd6f-4384-ac41-9054a7264aed
 12 30c74b52-fa15-43f5-9ef0-7559c42beba4
 13 27be28f5-f41c-665b-a4c8-d9789a475966
 14 f6f67c43-5dec-4a3c-9b3b-febc03893bb8
 15 ead502f3-f86b-13c4-8411-10d23e24b069
 16 ff1732f5-30b5-562a-a219-844e4611e533
 17 8ce90386-9d6a-2c31-9b4c-a4c235afbd7b

Explanation

Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 28602417384464152. Exactly this sequence comes out of new Random(246).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 0 of Run 2 (seed 1,054,905,639): new Random(1054905639), Next(8,24) per post. The RNG predicts N = 17; the post has N = 17 ✓. The seed is the machine's uptime in ms when the app started (boot 2012-06-14 10:26–10:31).
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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