201209271030 10kxwh

explained decrypted filler

3DES(name+title) ECB, 16 GUIDs, seed 602

Metadata

Post ID: 10kxwh
Title: 201209271030 → 2012-09-27 10:30 on A858's clock
Posted (UTC): 2012-09-27 20:30:01
Timezone: UTC−10 · title 10:30 against posted 20:30 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(A858DE45F56D9BC9201209271030) = 5e15d9a37e008ec484353060e1da40a4 (name+title)
New here: Missing from the community archive; decrypted here for the first time. (new results)
GUIDs: 16
Filler GUID seed: new Random(602).Next(9) ✓ verified
Run: Run 34 (seed 83,105,000) (seed)
Draw: 266 · predicted N = 16 ✓
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: 1,040 hex characters = 520 bytes = 65 8-byte 3DES blocks.
Derive the key. Password = A858DE45F56D9BC9201209271030 (name+title). Key = MD5(password) = 5e15d9a37e008ec484353060e1da40a4, 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 b352d999-19cf-29d2-943b-5d48a5cd225e
  2 6e81da5d-aeb4-4e64-ae12-5f95919f5c97
  3 83ed22ad-a16c-51b8-97a8-8163c1c4c364
  4 d73fe7ac-cc29-0aea-9938-fcf83d5edf95
  5 050101e7-d6ea-051d-8a79-b278f70601f1
  6 6231ee7f-cecf-5d79-a0c7-c04027d60932
  7 e8d2feb7-fee5-547c-8cce-c673c0de2065
  8 e7d53f5a-166d-4db7-828c-0b652f76b889
  9 00ad8d73-7d61-40d6-ad58-9f88b5e98a7c
 10 c4d9653e-7a5f-252b-9058-961072eddae8
 11 0ea91943-a60f-7ecf-ab5b-63ab9b1c8ad4
 12 1b36ec47-5714-4414-a550-c7aaa0a12f81
 13 6bbd9ffc-71d0-4824-8d35-17d8ddc8dfcd
 14 442f0923-b3ab-5fa5-8873-e85befce018d
 15 63ecd689-e67e-3a40-807e-08e60bb6ea30
 16 a72ca767-8037-8e08-831d-22c29fec8d58

Explanation

Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 2450055442744538. Exactly this sequence comes out of new Random(602).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 266 of Run 34 (seed 83,105,000): new Random(83105000), Next(8,64) 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 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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