201210041842 10yn0e

explained decrypted filler

3DES(name+title) ECB, 20 GUIDs, seed 963

Metadata

Post ID: 10yn0e
Title: 201210041842 → 2012-10-04 18:42 on A858's clock
Posted (UTC): 2012-10-04 22:42:34
Timezone: UTC−4 · title 18:42 against posted 22:42 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(A858DE45F56D9BC9201210041842) = 6d0c7842fd8553fcfd54c88efcf86e68 (name+title)
New here: Missing from the community archive; decrypted here for the first time. (new results)
GUIDs: 20
Filler GUID seed: new Random(963).Next(9) ✓ verified
Run: Run 35 (seed 854,622,578) (seed)
Draw: 188 · predicted N = 20 ✓
Machine boot: 2012-09-22 10:16–10:36 (seed = uptime at app start)
Sources: arctic-shift · body from arctic-shift
Links: Reddit · Arctic Shift · JSON
Score · comments: 2 · 0
Tags: automated (decryptable)2012Encrypted masked GUID listarctic-onlykey: name+titlerun: seed

From the post to its content

As posted (encrypted)

B0803A9F25695354 1B8328E4D757AF8B DB8F155D8E8835D8 72FAA38390DE5AF6 157F5538383B0C26 E52B802F4CE76E3E 367CB3890A2013A3 EC91FA62323E3893 6D59E390D31C5B86 5E9D5AAED3FFB74C 50E4038F5CF84F05 F6FDE455B4F23F1F B8359F5261D46074 52F6D4FC45A1C7A2 93A0E83153435354 29786C3113A3F226 DE560CAEBC46D2AE 339C45C9915C3DBD 435B32FAC2DC5DCC 244BD2621FA969C0 B748614EBA36233A 7CEF870CB7E5AB0B 018F9FEA4A0A7176 64E2AFAAF0939B6A 931687C66E93DA84 127AEA8CE73463F4 A63140B685A1B2CF DC81AB2C2ECBBC39 4318D237BAE2CED8 E5B9991CF3AC9F8F E96D8F45C9A2440C 6EB540D4A31134F6 E646721FDF3E1517 D707D5CE5AE433CF 8A5EE12114245119 17C43924B7F6E3D2 997025CC212E82E1 09EEE4232A855CEC DAD2D411EB32F57B 3FBCB748B9619BD7 9DE4D7AB273EDAE1 CD27A1635F140BB1 221B71A07BF7E63A 76C87164CA181664 6318B25F90EBB757 BB36B6652141B824 334377681CE346E9 0C26B81EEDC32AA3 D1D12F0744D0E4AB 629D9FE3F71880C7 7A529D2071598C24 2D5270C1A856AC52 BD106F8457881C81 A048A1476396C007 B3B45973DADFB92A 4A6E677F0426B4D2 DA9F4E89C9D31DA0 A37FC8A750B3CB70 C86EFD845F55CF00 864697ED8576A9BF 0E1D8455535CB2E6 C20D91D8D84747B8 89E8B0A784D2D6F3 93BCC9DC569A0C66 A54841F5A23FEE54 6E4EBC90EB95B840 767F7D08F6A4EDAB 530230911A6F3B0F 44CF8F33C560DB39 6D8A7310D8668C00 AB37CA4E3E06A3C8 3738B74DDCD4D53D 205919FAF172C94E 0F2295190AF0DF03 D527ABEB343DC296 CCC93A1FB4C598B7 4F3A3CCE2078B91C 58CF6105149C46E4 C0B27C2B55FE8524 E109C28FA3966719 0E4489157B4A53C5

Read the ciphertext. Strip whitespace: 1,296 hex characters = 648 bytes = 81 8-byte 3DES blocks.
Derive the key. Password = A858DE45F56D9BC9201210041842 (name+title). Key = MD5(password) = 6d0c7842fd8553fcfd54c88efcf86e68, 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 d7ff6516-315a-7cfe-aac4-dc9a1f7932cb
  2 95249941-bf04-3ec6-8194-71c2f4e846b1
  3 2ca5f646-1ad8-8330-b16d-9e047f444f1a
  4 cc134971-5f56-0b8d-bc85-b22dc6279f9f
  5 c5e2f7aa-878a-8ac3-9b1c-217053158516
  6 370c3c16-3a62-1c8e-94f5-8836372d822f
  7 40626039-fcbb-3e7e-9834-90d809f6c6a8
  8 d1564c20-2224-5000-bb0e-cd36f95e01d0
  9 aa63d504-a455-1b91-8f24-f6c627683fb0
 10 469043a1-8cc9-30a4-97ff-8347c3713961
 11 b01f45a5-c3d9-6836-aec0-89d039ef508e
 12 86399115-37cf-2fce-bec1-09557756863d
 13 83cb9e38-5935-5292-8e8c-447bff0d7adb
 14 dd5952d4-873f-4a11-b7f4-65007a9761fd
 15 6709fc35-728e-081c-845a-c562991a3fc2
 16 d6f5ce69-ef8a-3cac-aec7-5a4eb6a23aad
 17 3dcf87bf-d31e-6435-846b-97546d5c6f84
 18 b28fe75b-5c9c-01b8-ae9c-fd23279adbbb
 19 5352faf8-326a-651d-8a75-60c458811a22
 20 5da9e7ff-98b7-1e47-97aa-ea1a2d697672

Explanation

Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 73808135136254036061. Exactly this sequence comes out of new Random(963).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 188 of Run 35 (seed 854,622,578): new Random(854622578), Next(8,64) 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 2012-09-22 10:16–10:36).
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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