201309220632 1mvzw8

explained decrypted filler

seed 922

Metadata

Post ID: 1mvzw8
Title: 201309220632 → 2013-09-22 06:32 on A858's clock
Posted (UTC): 2013-09-22 10:32:53
Timezone: UTC−4 · title 06:32 against posted 10:32 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(A858DE45F56D9BC9201309220632) = 1cee82b192b004a8e538a9534238aa6a (name+title)
GUIDs: 20
Filler GUID seed: new Random(922).Next(9) ✓ verified
Run: Run 53 (seed 26,950,390) (seed)
Draw: 124 · 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: 2 · 1
Tags: automated (decryptable)2013Encrypted masked GUID listkey: name+titlerun: seed

From the post to its content

As posted (encrypted)

6B55A783D65A47F5 F256C0CFA2024EA0 1CAD6B8772A770B8 2C36442AD5C4A51B 524BBD791E62057D 9170FDDEDB864B49 1C7395D3D370C644 C0DB3D65C0259B94 7B6E8F8A4832639C B8125A94D77CF8CD CA04834396A7AA47 1DD265345537489B 998A7BA6EE463D0E 45927975F1516B1A 0FA0389269918637 5535E12C3BCDF351 F0E26374DCC365BD 32E5A79D0FF1CA47 BFBF6D382E2BA006 D12ECE26619162B5 8DFCADA0FA84E26A 3A091584267C7D79 F76C4047C02CE02F 9B2C29EF5C7CC8EB 4B7A3419690FDC2D EDA27BC548DCF48A 42D02516E670DAD9 B1E00D7191072A76 010616EB6387F0AE CFBBEC8737FA368E 7046E6FBAF02D5F4 1C0D7A306A9B84FE 9FE873CDC45D3FFB 78491F2A6F90E1E3 CBA78AB3B1F2538B E994905905014E2B 0A21A07D83FBDE3A 5DBAB39C15BF3B73 38007F120EFF2586 EB9C244138335282 819E878A4C06FC48 ABF5B00664830CB4 8E0060DE5E6EDD45 C744E3F664937F1E 482DDE143F53F024 5BB64B37116F0C07 74974DFD5260740D F8F86E193CA0A936 62483CD1F72CE9E2 CC8D385A11E5EB87 D7CC255F89F6B342 EFDDB429AB17CB74 DB62EE4CB871797D 77CD80DA64F99A82 856B680B38D35DFC 69A0136DC88888B5 ECEDB5562ECD1AA0 C81A913962DE2629 A7AE9FD635BE8EA2 EF0BF65C6B34F4F2 8F1E20CC6C3D2370 748A562A49D521AC 60D4085EEFCEA1DD 437BDE89F6B9E1D5 7F9140E4B9C64AED 5925A17433D78131 3504662D1F96745C 61F0E7FA79758321 63900774BBE7C07B 21941CB0228252CF 7A3823CED61C5EA0 D8C975CD18F50B79 19903F63DC6F3FC2 CF78745237921F46 A541EBA1655FCC6F EEE03F82E6E11CD6 89F599EC8FF36BB9 8B1F05D00B429391 DE931B4AE8BB4594 7B7983CD346F54C8 B1B23EF1EBC5DAD1

Read the ciphertext. Strip whitespace: 1,296 hex characters = 648 bytes = 81 8-byte 3DES blocks.
Derive the key. Password = A858DE45F56D9BC9201309220632 (name+title). Key = MD5(password) = 1cee82b192b004a8e538a9534238aa6a, 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 8cd9721f-40a1-3fc3-8e86-1c02f84556be
  2 87a68cf2-1c3a-3466-9b13-79fddecaa76f
  3 fc2a04f2-e63f-249c-99cf-2a6a1a4cfb2e
  4 5d84ffbd-597d-3076-ac30-4e64e0a35d2b
  5 de0df591-2931-4cae-b0cf-c4e9de3f49df
  6 7cb1df79-fff8-2abe-9b3b-8d65366ab1dd
  7 c7072b13-788b-0438-beab-e7db2bc74853
  8 8c1e1e59-2d00-88b8-9b85-d5a1fa6d8dfc
  9 55aadeb8-0333-0ecf-b762-5a22ece84c74
 10 ab86499f-7fee-2ac6-a8cc-7fe36b1d7697
 11 0d1c94df-17b6-5ff8-b3ce-33b27177fd9a
 12 0df49fca-8072-28f9-8a9d-577b515a978b
 13 ce0e5035-b423-441c-bfaf-b86de3041f9c
 14 8d74b0d5-662d-19a2-a0ad-9573df34e935
 15 dfb1e360-8a79-31c3-bc65-37d5afe8992b
 16 b113e702-06cc-770d-a8a5-fe711670c4c1
 17 b0bd5098-b4e4-324c-a4ec-78700ad35215
 18 f7d98951-c25f-51fc-af77-fca64ce8595f
 19 70d0dbb0-a88f-5e02-9c93-b1cabec3f614
 20 7b0851f2-2f3c-2b0b-b081-998fce5139b5

Explanation

Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 33234208025241373552. Exactly this sequence comes out of new Random(922).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 124 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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