201309271914 1na47n

explained decrypted filler

seed 108

Metadata

Post ID: 1na47n
Title: 201309271914 → 2013-09-27 19:14 on A858's clock
Posted (UTC): 2013-09-27 23:14:57
Timezone: UTC−4 · title 19:14 against posted 23:14 UTC
Author: [deleted]
Account: A858DE45F56D9BC9 main account
Subreddit: r/A858DE45F56D9BC9 the main subreddit
Category: F3 filler: 3DES(name/title) → GUID list, seed known
Size: 1,296 hex characters · 648 bytes
Cipher: 3DES-EDE2 (two-key Triple DES), ECB, PKCS7
Key: MD5(A858DE45F56D9BC9201309271914) = 6bb63b859b148b70bcf6d884d309d98b (name+title)
GUIDs: 20
Filler GUID seed: new Random(108).Next(9) ✓ verified
Run: Run 53 (seed 26,950,390) (seed)
Draw: 140 · predicted N = 20 ✓
Machine boot: 2013-09-12 09:30–10:30 (seed = uptime at app start)
Sources: community-archive, arctic-shift · body from community-archive
Links: Reddit · Arctic Shift · JSON
Score · comments: 10 · 6
Tags: automated (decryptable)2013Encrypted masked GUID listkey: name+titlerun: seed

From the post to its content

As posted (encrypted)

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

Read the ciphertext. Strip whitespace: 1,296 hex characters = 648 bytes = 81 8-byte 3DES blocks.
Derive the key. Password = A858DE45F56D9BC9201309271914 (name+title). Key = MD5(password) = 6bb63b859b148b70bcf6d884d309d98b, used as a two-key 3DES key.
Decrypt. 3DES-EDE2 in ECB mode, then strip the PKCS7 padding. The plaintext is 20 GUIDs as hex (shown below).

Decrypted: GUID list

  1 9e85efd5-3c5e-1099-a8b8-3ad34e898cf4
  2 6386b0e1-d6f6-48c1-8490-286a543ef5d4
  3 0348f69c-4bda-278f-8f70-750ebff06944
  4 835b2de4-f8fc-5c25-adfe-eb9b3b0a002a
  5 f752ae28-4075-88e1-9eff-4eb55c3f8b48
  6 9d8e75f3-dd62-8835-9f07-d41e972578f6
  7 f22fc75b-0649-2b77-8a41-1de6e9333133
  8 e4383165-00b3-5df1-8663-758e5e257ba9
  9 0c5ecd81-ff50-3a3f-ac61-fb0310ce58d7
 10 298c6e04-2e30-0847-b1b9-7e7cbfe1c280
 11 2d60034f-776d-7cf5-9f15-075b66c02cd5
 12 2ca32705-d78b-7ef2-aca1-a3fb935d7d3a
 13 31ac973e-a428-7bb1-8385-7dc33abbb895
 14 1448bfd8-9005-52d0-b854-6a0a8f42d00f
 15 e2f9006f-4f89-537e-8e23-e4df7fc40782
 16 167685ff-69a8-444f-9086-1a165e98ea07
 17 25853c58-e5c7-21b6-983d-182ec01a1f20
 18 87ee45c8-955d-81ad-b443-a73e28a81dd1
 19 eee3b0f2-c328-5260-97ce-672097f690af
 20 286b8344-ed65-122b-b197-c6d4a66e3458

Explanation

Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 14258825307775542851. Exactly this sequence comes out of new Random(108).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 140 of Run 53 (seed 26,950,390): new Random(26950390), 4·Next(1,12) per post. The RNG predicts N = 20; the post has N = 20 ✓. The seed is the machine's uptime in ms when the app started (boot 2013-09-12 09:30–10:30).
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

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