201210020620 10t66v

explained decrypted filler

3DES(name+title) ECB, 14 GUIDs, seed 282

Metadata

Post ID: 10t66v
Title: 201210020620 → 2012-10-02 06:20 on A858's clock
Posted (UTC): 2012-10-02 10:20:07
Timezone: UTC−4 · title 06:20 against posted 10:20 UTC
Author: [deleted]
Account: A858DE45F56D9BC9 main account
Subreddit: r/A858DE45F56D9BC9 the main subreddit
Category: F3 filler: 3DES(name/title) → GUID list, seed known
Size: 912 hex characters · 456 bytes
Cipher: 3DES-EDE2 (two-key Triple DES), ECB, PKCS7
Key: MD5(A858DE45F56D9BC9201210020620) = 5adaa0b1c600162a27309f3493f11410 (name+title)
New here: Missing from the community archive; decrypted here for the first time. (new results)
GUIDs: 14
Filler GUID seed: new Random(282).Next(9) ✓ verified
Run: Run 35 (seed 854,622,578) (seed)
Draw: 7 · predicted N = 14 ✓
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)

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

Read the ciphertext. Strip whitespace: 912 hex characters = 456 bytes = 57 8-byte 3DES blocks.
Derive the key. Password = A858DE45F56D9BC9201210020620 (name+title). Key = MD5(password) = 5adaa0b1c600162a27309f3493f11410, used as a two-key 3DES key.
Decrypt. 3DES-EDE2 in ECB mode, then strip the PKCS7 padding. The plaintext is 14 GUIDs as hex (shown below).

Decrypted: GUID list

  1 ce93c859-6e81-0576-83a2-c97c9c9fc6e6
  2 23b19d52-6573-58c1-8007-fee0694f2dbd
  3 a52d166d-856f-7798-9638-b48ec7065026
  4 3d9c2d0b-65f6-625a-b234-903cc9bba97e
  5 6d5e01ab-373f-4b33-896e-6e96fb4d878e
  6 8b296955-964f-85a2-96cf-321487daf163
  7 e4b2faca-95f9-2199-a0a1-e3560d578bee
  8 3d0e418a-4967-85ad-8af9-ecacb9bfed6d
  9 bce8bc77-e8d3-7414-9fbc-88b06b54b757
 10 7175eff0-29f0-2bbc-9957-1540099fd8f4
 11 128d3424-b74b-041d-a369-010b6f0f3e45
 12 8a487345-ee26-5472-b717-8c656626c811
 13 2823e218-1ca0-4647-af8d-60db4ca7d793
 14 c4ccf578-eea3-17cb-9f6b-f9a06c1ecce0

Explanation

Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 05764828720541. Exactly this sequence comes out of new Random(282).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 7 of Run 35 (seed 854,622,578): new Random(854622578), Next(8,64) per post. The RNG predicts N = 14; the post has N = 14 ✓. 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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