A858DE45F56D9BC9 archive

201209231930 10c5os

explained decrypted filler

3DES(name+title) ECB, 25 GUIDs, seed 975

Metadata

Post ID
10c5os
Title
201209231930 → 2012-09-23 19:30 on A858's clock
Posted (UTC)
2012-09-23 10:30:03
Timezone
UTC+9 · title 19:30 against posted 10:30 UTC
Author
[deleted]
Account
A858DE45F56D9BC9 main account
Subreddit
r/A858DE45F56D9BC9 the main subreddit
Category
F3 filler: 3DES(name/title) → GUID list, seed known
Size
1,616 hex characters · 808 bytes
Cipher
3DES-EDE2 (two-key Triple DES), ECB, PKCS7
Key
MD5(A858DE45F56D9BC9201209231930) = 4d31506178bd18442e7fb856a278bf02 (name+title)
New here
Missing from the community archive; decrypted here for the first time. (new results)
GUIDs
25
Filler GUID seed
new Random(975).Next(9) ✓ verified
Run
Run 34 (seed 83,105,000) (seed)
Draw
3 · predicted N = 25 ✓
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: 1,616 hex characters = 808 bytes = 101 8-byte 3DES blocks.
  • Derive the key. Password = A858DE45F56D9BC9201209231930 (name+title). Key = MD5(password) = 4d31506178bd18442e7fb856a278bf02, used as a two-key 3DES key.
  • Decrypt. 3DES-EDE2 in ECB mode, then strip the PKCS7 padding. The plaintext is 25 GUIDs as hex (shown below).

Decrypted: GUID list

  1 6ef157bf-5b51-0950-a8e6-11daafb619fe
  2 1526f959-7fb1-8414-a46a-705395ec475d
  3 e7f0b02b-02aa-2594-a200-adb9ceb2908b
  4 f2728d81-bb8f-5769-8de7-23bdf363f3e8
  5 5b208557-ebab-387e-9d75-df49b49ff41c
  6 c3413c76-c4ec-5fe7-b700-7ccd53fa9423
  7 4601bf13-5141-6077-b6c5-356248ebe0e6
  8 f55193af-5c97-56e9-bbde-a3cabe19057e
  9 532f620e-01f2-516e-94ee-059b9f1408cf
 10 3bf22748-8e0f-73d3-a317-db4be29135c6
 11 8347533e-4688-5c16-b6b4-eddc93bd554d
 12 2181a340-5626-515c-b90e-62a05433c181
 13 6065a82e-60e8-8e82-b0bd-1f7758c7abd4
 14 f13c2d96-75df-6bee-b3d7-789fb40a90a2
 15 f4a096f6-d8ac-4787-a247-d1906caebfd0
 16 53cccb37-7e8b-837f-9870-46de35a56de5
 17 46466c79-ee35-6a0e-9361-8eb1086047c6
 18 c2ed0c17-42d6-4bb1-90a9-fa092ab418fe
 19 6294ffd2-1b4c-096b-826c-575df2728769
 20 b98cce20-6719-7ec5-a0d7-fa1366dfae96
 21 2343299e-41a6-3840-a6d4-010ebb086c1b
 22 9f5017db-452c-0886-bb21-2ef7fe64eba8
 23 02beb43d-fa06-698c-8a8b-68f428b6f962
 24 5f41a04b-5710-5fd6-b96a-bb0569d093e9
 25 b00a252c-b47d-29f8-9a81-193f58b1fa40

Explanation

  1. Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 0825356557558648640730652. Exactly this sequence comes out of new Random(975).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.
  2. Explain the count. This post is draw 3 of Run 34 (seed 83,105,000): new Random(83105000), Next(8,64) per post. The RNG predicts N = 25; the post has N = 25 ✓. The seed is the machine's uptime in ms when the app started (boot 2012-09-22 10:23–10:24).
  3. Conclusion. Filler. The content is fully explained by the two RNGs.

Related

Findings: Mask digit · Count RNG & runs · New results