201209241317 10dls3

explained decrypted filler

3DES(name+title) ECB, 20 GUIDs, seed 832

Metadata

Post ID: 10dls3
Title: 201209241317 → 2012-09-24 13:17 on A858's clock
Posted (UTC): 2012-09-24 04:18:00
Timezone: UTC+9 · title 13:17 against posted 04:18 UTC
Author: [deleted]
Account: A858DE45F56D9BC9 main account
Subreddit: r/A858DE45F56D9BC9 the main subreddit
Category: F3 filler: 3DES(name/title) → GUID list, seed known
Size: 1,296 hex characters · 648 bytes
Cipher: 3DES-EDE2 (two-key Triple DES), ECB, PKCS7
Key: MD5(A858DE45F56D9BC9201209241317) = 33d3f834c15c75abc7ecd403a2155a70 (name+title)
New here: Missing from the community archive; decrypted here for the first time. (new results)
GUIDs: 20
Filler GUID seed: new Random(832).Next(9) ✓ verified
Run: Run 34 (seed 83,105,000) (seed)
Draw: 213 · predicted N = 20 ✓
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: 1,296 hex characters = 648 bytes = 81 8-byte 3DES blocks.
Derive the key. Password = A858DE45F56D9BC9201209241317 (name+title). Key = MD5(password) = 33d3f834c15c75abc7ecd403a2155a70, used as a two-key 3DES key.
Decrypt. 3DES-EDE2 in ECB mode, then strip the PKCS7 padding. The plaintext is 20 GUIDs as hex (shown below).

Decrypted: GUID list

  1 34e8930a-9505-305b-80ba-a8e0ad9672ae
  2 efcd9686-1e49-8eef-9f53-41f262cf2116
  3 65607543-82cc-2f42-8758-e90172699eb1
  4 1a9f5493-385e-1f9e-841d-3947b855ae7c
  5 8d9cf6f5-8d69-76f8-af0d-4aecbb49cfab
  6 132dd226-c483-5b73-9745-83fe8d272214
  7 15d51965-84f3-6d2d-bf20-5fdac02c2223
  8 84612d9b-c0ff-7d11-83d4-5925697bbf83
  9 c769d026-0f09-85fc-abf7-b2d528a7e9dc
 10 55e74c6a-9dc6-0f15-87d1-9896d7f9d3df
 11 73dbc570-16b3-277e-9b15-8a97c608fe50
 12 d1073222-081b-03d0-af59-cec9e21d072d
 13 b4345630-a58e-551d-acb2-82bbd90a8a54
 14 c265f57e-a9fc-23a7-9c87-77336704b7f0
 15 bbe9fa04-88be-358d-9a62-16b798bb4183
 16 8873af97-83f6-5fdc-80b1-1d4761d0cfd6
 17 ea08ffc4-c73c-582d-b0b2-d5074831273f
 18 55182f40-2e7f-7bdf-bed2-7d628828316d
 19 bbf548ea-9125-15ac-9006-5aff4f5d26f6
 20 ec4f2b15-9d07-4372-bbe7-6ae00ec9b136

Explanation

Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 38217567802052355714. Exactly this sequence comes out of new Random(832).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 213 of Run 34 (seed 83,105,000): new Random(83105000), Next(8,64) per post. The RNG predicts N = 20; the post has N = 20 ✓. 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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