A858DE45F56D9BC9 archive

201208170354 yc1c7

explained decrypted filler

3DES(name+title) ECB, 25 GUIDs, seed 769

Metadata

Post ID
yc1c7
Title
201208170354 → 2012-08-17 03:54 on A858's clock
Posted (UTC)
2012-08-16 18:54:18
Timezone
UTC+9 · title 03:54 against posted 18:54 UTC
Author
[deleted]
Account
A858DE45F56D9BC9 main account
Subreddit
r/A858DE45F56D9BC9 the main subreddit
Category
F3 filler: 3DES(name/title) → GUID list, seed known
Size
1,616 hex characters · 808 bytes
Cipher
3DES-EDE2 (two-key Triple DES), ECB, PKCS7
Key
MD5(A858DE45F56D9BC9201208170354) = bf80c5ed43c32b683308830f1ebc656a (name+title)
New here
Missing from the community archive; decrypted here for the first time. (new results)
GUIDs
25
Filler GUID seed
new Random(769).Next(9) ✓ verified
Run
Run 24 (seed 39,416,093) (seed)
Draw
20 · predicted N = 25 ✓
Machine boot
2012-08-15 10:18–10:21 (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 = A858DE45F56D9BC9201208170354 (name+title). Key = MD5(password) = bf80c5ed43c32b683308830f1ebc656a, 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 3933c256-582f-40b4-bf2c-a48a4c9efda6
  2 196207c0-5c08-482a-a3e1-831f5d71be02
  3 303b5c74-a859-2844-b735-43be6d27a01a
  4 69830d22-6feb-6850-b987-67c6f8276d40
  5 f1d4dd70-133f-35f5-8c32-c03bca52d653
  6 7f57974a-fdc2-566d-b0e9-c314c78f556d
  7 48cfafe3-505f-4857-b3f6-fff311d4ce74
  8 9bd854fa-55af-28d4-acc3-7c7d484411ee
  9 717661a8-6115-1820-b136-2dcd22fd1754
 10 65fd2d00-123d-712a-a79b-538ffe1a3c02
 11 f7be428d-afd6-77b3-be07-65867f69f330
 12 9e8ea45c-fb13-72de-9dc9-220ad2403edb
 13 b6063e01-209a-2c30-9dca-5f872431a161
 14 7950c8fe-f848-4c88-8f98-0c2316c2904e
 15 e29d3378-8727-2a49-abb9-c9ebd3c4f1cc
 16 b37c19f3-fccd-2221-a3ea-6690b899e486
 17 5e3ca330-3a9b-1621-8be6-a7e78631805f
 18 47f0e05f-99bc-637f-aba7-60cdad7471fb
 19 9d796dba-49c5-47f4-ab57-2f10fd515109
 20 62828a0d-aea6-0554-b493-ae3f8c5aac9d
 21 209a560c-cbdf-8cff-868d-0f1d73422a3e
 22 5fc3dbdd-6f86-4f54-9b39-09c4949e806f
 23 e6b9403f-0d12-804c-97cc-29682a191cb6
 24 25ed0eda-cc3d-6a51-8d23-ff40890a57be
 25 e3de8641-8721-03c3-b32c-8bd5f385d281

Explanation

  1. Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 4426354217772422164084860. Exactly this sequence comes out of new Random(769).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 20 of Run 24 (seed 39,416,093): new Random(39416093), 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 2012-08-15 10:18–10:21).
  3. Conclusion. Filler. The content is fully explained by the two RNGs.

Related

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