201309211232 1mueac

explained decrypted filler

seed 923

Metadata

Post ID: 1mueac
Title: 201309211232 → 2013-09-21 12:32 on A858's clock
Posted (UTC): 2013-09-21 16:32:54
Timezone: UTC−4 · title 12:32 against posted 16:32 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(A858DE45F56D9BC9201309211232) = aec70e9d238cd531107c7cd7fd0e23df (name+title)
GUIDs: 20
Filler GUID seed: new Random(923).Next(9) ✓ verified
Run: Run 53 (seed 26,950,390) (seed)
Draw: 121 · 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: 4 · 1
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 = A858DE45F56D9BC9201309211232 (name+title). Key = MD5(password) = aec70e9d238cd531107c7cd7fd0e23df, 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 e3f8dfe5-4077-8186-b6d4-be94c5038a73
  2 54472e26-a4d0-51c2-89c6-5246c6a4062e
  3 3a61019f-4670-84f2-b2bb-c4e7ed6490c5
  4 f1b09771-073a-5820-9693-9ae3fcc1007d
  5 4dfeb158-c17f-88c6-abad-8ddb29d41182
  6 64058c3f-8e6e-140b-9cfd-3d443c279176
  7 ebee6f08-9110-4aa1-ad76-b40db4490d80
  8 ac6d93a9-6d0c-4fef-b197-a7cd1fb4b308
  9 e5920bd1-a839-1e2c-a4d4-66586ab58383
 10 d5cead5b-f94b-53d9-9c65-8adb33927e81
 11 36fd2023-caa1-2225-9515-1e517c7fda9a
 12 3c79f24e-b20b-00e8-964c-9111eb97b2bc
 13 9b73a7cf-9964-185d-aea8-510e41687adb
 14 d2005c41-3f37-5103-b0cf-dc2e19d2665f
 15 3911d137-3353-081a-aea2-b56803a8094e
 16 1cc59b41-24c6-489f-9f5b-f3eb01731b21
 17 736f0a21-5323-749d-bfe5-c5da3f880959
 18 1641f35f-d6ed-23c5-a4a7-8a56630e5de1
 19 12f0c344-65a7-5561-94ca-30407bfdbd4b
 20 05541a9b-a520-6b57-994f-4546ac2759ad

Explanation

Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 85858144152015047256. Exactly this sequence comes out of new Random(923).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 121 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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