201210071005 1135d1

explained decrypted filler

3DES(name+title) ECB, 13 GUIDs, seed 983

Metadata

Post ID: 1135d1
Title: 201210071005 → 2012-10-07 10:05 on A858's clock
Posted (UTC): 2012-10-07 14:05:06
Timezone: UTC−4 · title 10:05 against posted 14:05 UTC
Author: [deleted]
Account: A858DE45F56D9BC9 main account
Subreddit: r/A858DE45F56D9BC9 the main subreddit
Category: F3 filler: 3DES(name/title) → GUID list, seed known
Size: 848 hex characters · 424 bytes
Cipher: 3DES-EDE2 (two-key Triple DES), ECB, PKCS7
Key: MD5(A858DE45F56D9BC9201210071005) = 34d8d01e7186ae2fb9f8169b0ce9eaaf (name+title)
New here: Missing from the community archive; decrypted here for the first time. (new results)
GUIDs: 13
Filler GUID seed: new Random(983).Next(9) ✓ verified
Run: Run 35 (seed 854,622,578) (seed)
Draw: 378 · predicted N = 13 ✓
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: 1 · 0
Tags: automated (decryptable)2012Encrypted masked GUID listarctic-onlykey: name+titlerun: seed

From the post to its content

As posted (encrypted)

6A86DC11EBC5CE21 81F6EE40312FA0ED A3CA0A2CA8C038F6 25CC2C43E08477FA 1F3A29D13E1F59BC 1EA385A6250EC18F 52CE670B4910F9FD 09914DF2BD6D1C1E 8EF7F6DFF1E187B3 9FE5490D66566DA5 717D6DAB34529F2E 1C9F3AF5F5DB6D69 FDD707D067284AF9 FC7F93EEC63108E6 65F4F91AD4FF174B E275764EE52B02E7 4A3FC061D9E57A95 6404F1893B0BEEEF 849999A39D39DEDA DEC2E0F66A1DF4F2 6F564E53A1C22C63 0A4EA888D8FFF119 0CFFD6F025573EC9 946C0C81BC6D72B5 913350731931B66F 69EE733DC2FEB0E8 E3715D5E5EC606C5 DD33B1B2DD803509 96400E4F220898C1 61021FBA61020380 33847B89B1DF8B57 261920201AB7BD82 DF7358664DD7D118 6E15CBB060FE5273 D1BA14CB13843B10 A87E9B73C612D695 50D6B3019F455074 37DD4C1CE88C5F18 6E98BF738EB19B42 DD369F9C70D03571 B435BB946825CD82 7AD492310A13EE2E 5ED69B1A0E1A2848 C2A22F33B58498D1 54855B29ADA5CBE6 067341E2D13EB1DB 2AECEAC2CD531A00 C2CEC47779696910 FA5D4A01B21712AB B00781F469A8F25D A2043BA9E3287DC5 6EDFBD42E94D199C 64242F290A6EC7D4

Read the ciphertext. Strip whitespace: 848 hex characters = 424 bytes = 53 8-byte 3DES blocks.
Derive the key. Password = A858DE45F56D9BC9201210071005 (name+title). Key = MD5(password) = 34d8d01e7186ae2fb9f8169b0ce9eaaf, used as a two-key 3DES key.
Decrypt. 3DES-EDE2 in ECB mode, then strip the PKCS7 padding. The plaintext is 13 GUIDs as hex (shown below).

Decrypted: GUID list

  1 db96e96e-9b4e-286f-a486-ae6172b5ea86
  2 982570b5-7d7a-2257-ab44-88b650383af3
  3 95ff2b3e-4a02-711f-999a-8c9fd0812c15
  4 1cec2bab-a96e-3366-b212-530340c267ef
  5 f0bbf4bb-7243-02bd-aa16-4d67be5b4ba4
  6 b710fff0-7e3a-5634-9ed6-461728be9581
  7 18d8e40f-520d-31dd-aa0c-0e34d75ec4c5
  8 29a22f38-d99e-5a6c-8e28-44132f4a443f
  9 e7cfbbc4-7467-5be4-9e7c-5a28e659c47d
 10 d4c16199-8ba3-6b9e-a8a0-c326d5ef26d2
 11 2f809541-f140-4ed8-a3c0-c12972e42333
 12 aa3102d5-2272-8cb1-9ac2-ccb27d39fe87
 13 017d77b1-c05d-3c28-9946-33bc0891c2ad

Explanation

Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 2273053556483. Exactly this sequence comes out of new Random(983).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 378 of Run 35 (seed 854,622,578): new Random(854622578), Next(8,64) per post. The RNG predicts N = 13; the post has N = 13 ✓. 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

Related