A858DE45F56D9BC9 archive

201208031800 xn4ck

explained decrypted filler

seed 216

Metadata

Post ID
xn4ck
Title
201208031800 → 2012-08-03 18:00 on A858's clock
Posted (UTC)
2012-08-03 21:57:43
Timezone
UTC−4 · title 18:00 against posted 21:57 UTC
Author
[deleted]
Account
A858DE45F56D9BC9 main account
Subreddit
r/A858DE45F56D9BC9 the main subreddit
Category
F3 filler: 3DES(name/title) → GUID list, seed known
Size
2,128 hex characters · 1,064 bytes
Cipher
3DES-EDE2 (two-key Triple DES), ECB, PKCS7
Key
MD5(A858DE45F56D9BC9A858DE45F56D9BC9) = 0dcc4bd9e114ebc42078977dc9125404 (name+name)
GUIDs
33
Filler GUID seed
new Random(216).Next(9) ✓ verified
Run
Run 22 (seed 528,385,484) (seed)
Draw
11 · predicted N = 33 ✓
Machine boot
2012-07-27 19:02–19:13 (seed = uptime at app start)
Sources
community-archive, arctic-shift · body from community-archive
Links
Reddit · Arctic Shift · JSON
Score · comments
7 · 0
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: 2,128 hex characters = 1,064 bytes = 133 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 33 GUIDs as hex (shown below).

Decrypted: GUID list

  1 388c08f8-d7de-5dba-8935-3abfc7ebcc74
  2 e2556bbe-d41f-158f-8e65-29896cf2be01
  3 44fecccc-dc21-6e8e-8512-4600e372607b
  4 7e105677-edbe-5417-8661-10e4c8f900c4
  5 7fde317f-97b7-6e8a-9904-a211fda7b73a
  6 1f10bcfc-6468-2aea-a3bf-da3344b1c878
  7 09008ee7-7522-6709-a823-49e04efc066e
  8 d501c4e0-c6b7-740b-a9ce-27234dedc504
  9 f1c9b5eb-5ab0-6c3b-95e5-5b221b287ab7
 10 32f48a3b-7ccb-8483-937d-875d194f130a
 11 6e80cdbd-89ed-3510-abb8-acbe6b811186
 12 9b19ab86-85cb-08c7-97e6-413a48762f1a
 13 e306c5b2-0bd5-1169-abc4-939588a2d423
 14 3d8e47a1-ca8a-71f9-a4fd-8f022d4613fd
 15 531c3368-afa2-1951-bbcc-6eef9b59bf2f
 16 4dc57341-e87a-8b16-8503-ff8133f20b85
 17 9214fce8-8aa1-57e7-8f63-732837d293c7
 18 087f62cb-40c3-87e1-a751-f0a4ca4de01f
 19 9b02bec9-f45f-4a36-8072-a05f16cc5da6
 20 ef99e301-cf79-82b2-90ff-6d3180a5a5c8
 21 d3f6e604-1151-48ba-b415-35ebe19ceb7d
 22 0d414d74-bdd4-72cd-af63-caec3941dc1d
 23 4d561dc9-d0a3-4b8d-bdb3-7eca982dfebe
 24 e3ee5eb9-7e42-4bed-8c14-dfce2fb90c1d
 25 03a2c795-dd99-7ac5-abda-2a8ca0941ef0
 26 35da6566-3c22-45b6-bb62-348165fefac1
 27 80802d5d-3985-5ea8-95b6-0f54f538e02c
 28 9a9e5028-b993-47b5-93f4-549ac1c6abca
 29 b24e955b-5ee2-1b93-9588-d7213668a70b
 30 6ca6eab6-2033-0bdf-a105-ba5ee7080819
 31 89609540-01d3-88f1-8614-beb3be800bae
 32 8d0d42b2-c11c-397a-9914-1e24fe20b017
 33 5e70889e-9394-1365-a253-a0f79a0d5446

Explanation

  1. Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 516562676830171858484744745410831. Exactly this sequence comes out of new Random(216).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 11 of Run 22 (seed 528,385,484): new Random(528385484), Next(8,64) per post. The RNG predicts N = 33; the post has N = 33 ✓. The seed is the machine's uptime in ms when the app started (boot 2012-07-27 19:02–19:13).
  3. Conclusion. Filler. The content is fully explained by the two RNGs.

Related

Findings: Mask digit · Count RNG & runs