201206271055 vnyty

explained decrypted filler

3DES(name) ECB, 16 GUIDs, seed 320

Metadata

Post ID: vnyty
Title: 201206271055 → 2012-06-27 10:55 on A858's clock
Posted (UTC): 2012-06-27 02:54:08
Timezone: UTC+8 · title 10:55 against posted 02:54 UTC
Author: [deleted]
Account: A858DE45F56D9BC9 main account
Subreddit: r/A858DE45F56D9BC9 the main subreddit
Category: F3 filler: 3DES(name/title) → GUID list, seed known
Size: 1,040 hex characters · 520 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: 16
Filler GUID seed: new Random(320).Next(9) ✓ verified
Run: Run 6 (seed 652,173,660) (seed)
Draw: 27 · predicted N = 16 ✓
Machine boot: F 2012-05-15 19:06–19:16 (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: namerun: seed

From the post to its content

As posted (encrypted)

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

Read the ciphertext. Strip whitespace: 1,040 hex characters = 520 bytes = 65 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 16 GUIDs as hex (shown below).

Decrypted: GUID list

  1 e3642f18-97e5-86c1-9657-d44e55d1008a
  2 cd73efe8-485d-6c9f-b544-15fa0cd51b07
  3 00c3aa69-e3d3-39ba-b484-7d612ead4915
  4 d1fcc1c7-3513-7ba6-8d3a-f571d8bfb132
  5 6bbb9bab-4378-6012-a2ff-63439c7f97c8
  6 80aa14f9-c4a2-13e4-a12b-323b4aa71403
  7 a02fa5a1-99a0-2af1-b5a4-885b5ef5522c
  8 250dedb5-60db-86dd-b536-741053fbe210
  9 2c0853b1-5695-50f7-9adb-fdeb85c92acf
 10 e0a1a955-8b05-2665-891d-dec356d7784e
 11 b8a142cb-2ec1-0192-8e22-943cda0f97bb
 12 6a0d4620-e2a5-298d-b7b0-b9c1c951bf3c
 13 83b7723f-c3b2-5618-a74b-4b58881eda92
 14 835c429e-57cb-80e8-811c-f6a8410ce1cf
 15 2eff91b0-d134-83b9-afee-843a0e0a94d1
 16 173266de-90c0-728a-8874-158b28dbab76

Explanation

Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 8637612852025887. Exactly this sequence comes out of new Random(320).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 27 of Run 6 (seed 652,173,660): new Random(652173660), Next(8,24) per post. The RNG predicts N = 16; the post has N = 16 ✓. The seed is the machine's uptime in ms when the app started (boot F 2012-05-15 19:06–19:16).
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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