A858DE45F56D9BC9 archive

201207081343 w87p3

explained decrypted filler

seed 797

Metadata

Post ID
w87p3
Title
201207081343 → 2012-07-08 13:43 on A858's clock
Posted (UTC)
2012-07-08 17:41:42
Timezone
UTC−4 · title 13:43 against posted 17:41 UTC
Author
[deleted]
Account
A858DE45F56D9BC9 main account
Subreddit
r/A858DE45F56D9BC9 the main subreddit
Category
F3 filler: 3DES(name/title) → GUID list, seed known
Size
2,000 hex characters · 1,000 bytes
Cipher
3DES-EDE2 (two-key Triple DES), ECB, PKCS7
Key
MD5(A858DE45F56D9BC9A858DE45F56D9BC9) = 0dcc4bd9e114ebc42078977dc9125404 (name+name)
GUIDs
31
Filler GUID seed
new Random(797).Next(9) ✓ verified
Run
Run 14 (seed 205,976,312) (seed)
Draw
9 · predicted N = 31 ✓
Machine boot
2012-07-05 08:28–12:28 (seed = uptime at app start)
Sources
community-archive, arctic-shift · body from community-archive
Links
Reddit · Arctic Shift · JSON
Score · comments
7 · 2
Tags
automated (decryptable)2012Encrypted masked GUID listkey: name+namerun: seed

From the post to its content

As posted (encrypted)

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
  • Read the ciphertext. Strip whitespace: 2,000 hex characters = 1,000 bytes = 125 8-byte 3DES blocks.
  • Derive the key. Password = A858DE45F56D9BC9A858DE45F56D9BC9 (name+name). Key = MD5(password) = 0dcc4bd9e114ebc42078977dc9125404, used as a two-key 3DES key.
  • Decrypt. 3DES-EDE2 in ECB mode, then strip the PKCS7 padding. The plaintext is 31 GUIDs as hex (shown below).

Decrypted: GUID list

  1 afb3be58-9a2d-03f6-8a4a-e7d0cf62979c
  2 cf16cc68-d0c9-6e2f-b53b-812bf87bb8a2
  3 de209e93-08b3-770a-9094-0b75e8ad3503
  4 0acbe577-e924-65f2-a8c8-b7c6dc1a8b2b
  5 2b8ea18b-e6a7-00c3-87ae-8fe224fcd7e0
  6 0bc5d45d-3ff8-083e-81a2-a2e4189f4c43
  7 9dd3668e-7689-0054-8dbb-16d4a764e3a5
  8 b2f8f955-9b0c-2818-b1b0-310ce7d9c4d7
  9 aeb46eeb-8cbb-5bfa-94b4-2c309ae5226c
 10 c365224f-611b-1863-80d1-9a28ab87ad47
 11 acf0a862-3421-47e7-b592-5468531def1d
 12 9e001310-753d-6066-bb1c-ab774202a7e2
 13 1d7d8257-bf5f-4e48-8ad4-501621f4cc55
 14 b3b69856-63cc-15fe-861a-4069e69ab0fc
 15 13ce5c4b-c17c-76d9-b405-346215311dac
 16 aea565eb-e659-6cc4-819e-5cc9762c3bfb
 17 2b719704-36a9-7e42-9660-7623b921319a
 18 1855294f-941b-1a11-9bac-5f4beaa530a7
 19 ad8e7677-3efb-206b-bcb6-ead73e53f296
 20 5de5bcd9-0f3a-80f7-99d4-b4d42b8b1b05
 21 85704553-8afb-6796-8301-ce6ccc5b3f7c
 22 323d16a3-5b70-3b0d-bc04-c094c6e69cee
 23 5d944c39-5b0b-6284-ac5b-ff787226a108
 24 e3d5fc7c-d1be-4179-b76d-368ce9b8af43
 25 4c89371f-797f-792a-81b4-e252ebe8b367
 26 5e95f46e-f366-12a3-93f4-2b2b56639365
 27 a38863d0-fcd4-1bf6-b84e-7361db1881e6
 28 45c5fa34-32fa-4217-9c30-f206d6297ff4
 29 8e01f85c-a864-6249-ab42-b76bb0d77999
 30 a5de0dd8-06b0-852c-b057-2148af576d10
 31 1a733939-b20e-3c94-9faf-a072ce7e2c5b

Explanation

  1. Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 0676000251464176712863647114683. Exactly this sequence comes out of new Random(797).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 9 of Run 14 (seed 205,976,312): new Random(205976312), Next(8,64) per post. The RNG predicts N = 31; the post has N = 31 ✓. The seed is the machine's uptime in ms when the app started (boot 2012-07-05 08:28–12:28).
  3. Conclusion. Filler. The content is fully explained by the two RNGs.

Related

Findings: Mask digit · Count RNG & runs