201206271316 vo6gq

explained decrypted filler

seed 290

Metadata

Post ID: vo6gq
Title: 201206271316 → 2012-06-27 13:16 on A858's clock
Posted (UTC): 2012-06-27 05:14:25
Timezone: UTC+8 · title 13:16 against posted 05:14 UTC
Author: [deleted]
Account: A858DE45F56D9BC9 main account
Subreddit: r/A858DE45F56D9BC9 the main subreddit
Category: F3 filler: 3DES(name/title) → GUID list, seed known
Size: 1,232 hex characters · 616 bytes
Cipher: 3DES-EDE2 (two-key Triple DES), ECB, PKCS7
Key: MD5(A858DE45F56D9BC9) = 34a14a42e98ff96095af56604e290cae (name)
GUIDs: 19
Filler GUID seed: new Random(290).Next(9) ✓ verified
Run: Run 6 (seed 652,173,660) (seed)
Draw: 41 · predicted N = 19 ✓
Machine boot: F 2012-05-15 19:06–19:16 (seed = uptime at app start)
Sources: community-archive, arctic-shift · body from community-archive
Links: Reddit · Arctic Shift · JSON
Score · comments: 6 · 1
Tags: automated (decryptable)2012Encrypted masked GUID listkey: namerun: seed

From the post to its content

As posted (encrypted)

E0F0BD3681178A23 76352570319AFD36 7FC0C414EBB47956 543A34CEBD0763D9 59D2863535D8F1C7 086F8D6C0CC6F9A7 5D3F5D170F556AF7 45A601E4A97E56B4 8F7CB2950D4DAECC 13B495A8065D8B00 978D007DDE868789 6EF82AE621D30587 8459BDE0B8CD03BC 41803C1B2B4FC62E 3ACD292253BA9A37 BDE8981EA6BFADBB 5298E05D065105F6 B2E871905B0EE63C 0B02E13AE00E627F E5F4D274B74D6159 D8AB0435987D18AB 4C36D6C8FBFE31A6 A15040B237AC0762 F4400821BCCFAA75 D8E7F83200635CF2 488D1EDC6491B527 B20AB650BD277941 9F76DE5DDAFB3E58 66E7535855246A63 FBD7236706578379 A85D76E1DECF9D81 781D01E3BADBD781 38ADA2F4867C0D3A E5185FCFC043EA5D 2B78E6695324B1CE C8412BD115033F39 EA199CD91B6E7FEF F016A806882E4068 85D32171E01A54B1 5FA019F6189397FD F15722099F578C4D 8F227F44DF3347E5 C628A58A36F0B84D F03FF6F84F184F71 30EE6967940D0C80 6FD4A447C474DC0E 35054D8120465041 BE3FBC80B529B49D 30FB8CDA1867CB7B ED14510197F78F9E C0221106CA227D81 0DCF76B73673CA60 6F437F64B12947DF 0E4605C128E911B7 F4566297A037B104 32B3923A94AC740B 363D7EA1D08F22AA 44D7497D46A53C3C 67AA684FD16432F5 B432A276F7FDD420 B69613CBFDBBD4FA D447C196B8F5BE86 9D3786B2BE442028 678480C528DC9A26 558409D3522970B1 ECC0854AEDC0A1A1 7982467FFC9D7FA7 B01D048AE40197DB 1FDC1F1B4242ED1F 6674C2EF68E61E31 8C22E6AB96F05A60 3E2ED6BDFEDAD927 BEF3047F5BF272AD 9CE02557D106E763 07A4BD1C67640E7B 1745F0351B4A299B 5DACFFBA8FF64DBD

Read the ciphertext. Strip whitespace: 1,232 hex characters = 616 bytes = 77 8-byte 3DES blocks.
Derive the key. Password = A858DE45F56D9BC9 (name). Key = MD5(password) = 34a14a42e98ff96095af56604e290cae, used as a two-key 3DES key.
Decrypt. 3DES-EDE2 in ECB mode, then strip the PKCS7 padding. The plaintext is 19 GUIDs as hex (shown below).

Decrypted: GUID list

  1 7d123213-c3d3-275a-8cc4-c97696c4c2e0
  2 e3885033-d3f9-8f8b-aa16-37f8adcb8815
  3 68ad45c8-77c0-4237-a12a-94e2df474bb0
  4 16df9a86-77e1-40a4-9c8d-2da284d071fb
  5 51f122ce-e60f-1e03-a062-e9d2bf2741e8
  6 f38c2da5-7b30-8fd0-b095-7d67a4283247
  7 373f1a33-18f7-728d-a600-900206886579
  8 d254df0d-5146-8688-ba55-3045698245ea
  9 177e2f4e-f0e8-781c-8582-97bb430f6180
 10 4bfdad6a-3ea2-11cf-a07c-161834edeb30
 11 b1b7fc62-3b70-8602-8d66-dcb51f90f666
 12 2b03fa40-bce7-7ffb-afca-bfa48d35efb7
 13 e8f3ab4e-1dbe-8a92-adea-6b5158913844
 14 d67182f6-bdb2-3a2d-85d7-a8a64bd13f8b
 15 69a6b56d-4320-8b46-8c14-40ac0ae42af4
 16 34ef0514-1d06-1e69-94fc-56b245ea91ef
 17 ca51abe7-0dc5-69ab-b60f-daddbfc9b8d3
 18 24163ee0-b6d5-71c4-abb5-226a744ed77e
 19 d46de2b6-40c7-42cf-8b9b-c24e5b8e051e

Explanation

Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 2844187871878381674. Exactly this sequence comes out of new Random(290).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 41 of Run 6 (seed 652,173,660): new Random(652173660), Next(8,24) per post. The RNG predicts N = 19; the post has N = 19 ✓. The seed is the machine's uptime in ms when the app started (boot F 2012-05-15 19:06–19:16).
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

Related