201209241324 10dm3u

explained decrypted filler

3DES(name+title) ECB, 21 GUIDs, seed 733

Metadata

Post ID: 10dm3u
Title: 201209241324 → 2012-09-24 13:24 on A858's clock
Posted (UTC): 2012-09-24 04:24:04
Timezone: UTC+9 · title 13:24 against posted 04:24 UTC
Author: [deleted]
Account: A858DE45F56D9BC9 main account
Subreddit: r/A858DE45F56D9BC9 the main subreddit
Category: F3 filler: 3DES(name/title) → GUID list, seed known
Size: 1,360 hex characters · 680 bytes
Cipher: 3DES-EDE2 (two-key Triple DES), ECB, PKCS7
Key: MD5(A858DE45F56D9BC9201209241324) = 79d8d8b3eeb0fa63688a563501cffd18 (name+title)
New here: Missing from the community archive; decrypted here for the first time. (new results)
GUIDs: 21
Filler GUID seed: new Random(733).Next(9) ✓ verified
Run: Run 34 (seed 83,105,000) (seed)
Draw: 219 · predicted N = 21 ✓
Machine boot: 2012-09-22 10:23–10:24 (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: 1,360 hex characters = 680 bytes = 85 8-byte 3DES blocks.
Derive the key. Password = A858DE45F56D9BC9201209241324 (name+title). Key = MD5(password) = 79d8d8b3eeb0fa63688a563501cffd18, used as a two-key 3DES key.
Decrypt. 3DES-EDE2 in ECB mode, then strip the PKCS7 padding. The plaintext is 21 GUIDs as hex (shown below).

Decrypted: GUID list

  1 f9ca7259-ee3c-5443-b82c-1102323169f2
  2 70837347-a0f3-849c-a9d2-c411988f5dca
  3 a147a5e4-a93b-124f-abdd-c2ed79e1e066
  4 20c14d8c-1b27-0094-9628-bfb45e4cf3bb
  5 24570db8-fdb6-1455-b847-a89b939f7af7
  6 f2f094de-46bc-1e82-b69e-2857502afcdc
  7 05e248bf-d778-23f5-b836-322ea37f1592
  8 a422a72c-655a-1fd5-8966-43bb8e6d1e4e
  9 0c096e08-a815-5210-978d-ba4b0dd7eb01
 10 718baa0b-1759-52c9-b64a-98df45867fdb
 11 9642e451-14d8-2ae4-8499-9cadf97c14c1
 12 f192f5e6-cf1a-60de-b896-ba63749d3d88
 13 87fa5ad2-7fd4-4b50-b8a1-afc0e8367f13
 14 1aa6ecbd-1f13-7b92-9a95-473dbe50b165
 15 2dd930df-2c60-0b9f-b9e9-4240254b0582
 16 2ea942b3-42ef-7775-ba18-d41a3e48bf39
 17 bf375eac-0702-8fdb-87b4-0e9eeb45772a
 18 e9d8b337-0cc8-4df4-b94d-04a80d0306fc
 19 1e9f171c-79ff-4a81-9543-dc12dc38cf90
 20 487dc22a-fc58-1d36-bd10-630a63446289
 21 fbbcc87d-458e-1814-a828-1c5769b602b9

Explanation

Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 581011215526470784411. Exactly this sequence comes out of new Random(733).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 219 of Run 34 (seed 83,105,000): new Random(83105000), Next(8,64) per post. The RNG predicts N = 21; the post has N = 21 ✓. The seed is the machine's uptime in ms when the app started (boot 2012-09-22 10:23–10:24).
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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