201209241241 10djrx

explained decrypted filler

3DES(name+title) ECB, 23 GUIDs, seed 907

Metadata

Post ID: 10djrx
Title: 201209241241 → 2012-09-24 12:41 on A858's clock
Posted (UTC): 2012-09-24 03:41:34
Timezone: UTC+9 · title 12:41 against posted 03:41 UTC
Author: [deleted]
Account: A858DE45F56D9BC9 main account
Subreddit: r/A858DE45F56D9BC9 the main subreddit
Category: F3 filler: 3DES(name/title) → GUID list, seed known
Size: 1,488 hex characters · 744 bytes
Cipher: 3DES-EDE2 (two-key Triple DES), ECB, PKCS7
Key: MD5(A858DE45F56D9BC9201209241241) = fbb14ef2a8d474978f21a358ee88dc58 (name+title)
New here: Missing from the community archive; decrypted here for the first time. (new results)
GUIDs: 23
Filler GUID seed: new Random(907).Next(9) ✓ verified
Run: Run 34 (seed 83,105,000) (seed)
Draw: 177 · predicted N = 23 ✓
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: 1,488 hex characters = 744 bytes = 93 8-byte 3DES blocks.
Derive the key. Password = A858DE45F56D9BC9201209241241 (name+title). Key = MD5(password) = fbb14ef2a8d474978f21a358ee88dc58, used as a two-key 3DES key.
Decrypt. 3DES-EDE2 in ECB mode, then strip the PKCS7 padding. The plaintext is 23 GUIDs as hex (shown below).

Decrypted: GUID list

  1 a640e745-2bd6-5e0a-a7ac-11fbf04dc94d
  2 1ac501a4-a067-8e2a-b221-eec7713fdaa9
  3 51dcd750-d769-606b-b590-869e0032f731
  4 f8d863eb-6827-196b-ba4b-8c8fa6db5185
  5 a4480297-e408-6851-b8df-7a87a5da3b84
  6 9b1ce132-98d8-17f0-8e65-3926fa29219a
  7 a46730c6-2126-295c-a425-77acd85d22d3
  8 9ad37af0-65d1-4931-80cb-666e62619ccf
  9 d6f06bd7-7612-16da-9903-eef42011f18c
 10 3a8230fd-6068-68ab-952f-f340d7a74ce7
 11 99e7fe06-fc27-401f-b480-8e22cff8c956
 12 b285771b-3699-50fc-a82b-95840ea0ca08
 13 ec38e6d3-2735-1cc9-90f4-2dfd7b56a166
 14 ac557ac8-d841-394d-a515-52327b45682d
 15 e6aa1feb-5d75-728b-8fc7-8bbeb1915044
 16 f9ef5c2e-cea0-4303-97f1-75b14075080d
 17 53c9a1d6-982f-1e1b-a922-3761e4bfd361
 18 d57a1ac0-2e2c-3500-a240-4afb826e6dbb
 19 bdf5a204-9f69-2d13-af50-af3163640292
 20 8f919752-7a91-4675-8236-cc47953592bc
 21 0cabaeea-63e3-2f18-ae69-cdbe670b297a
 22 8cd5b36d-3ded-3d74-acf2-c8bc3831c19a
 23 57da109d-6994-24bc-a2bc-84b1e53ed5c3

Explanation

Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 58616124164513741324232. Exactly this sequence comes out of new Random(907).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 177 of Run 34 (seed 83,105,000): new Random(83105000), Next(8,64) per post. The RNG predicts N = 23; the post has N = 23 ✓. 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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