201210061504 111wus

explained decrypted filler

3DES(name+title) ECB, 13 GUIDs, seed 267

Metadata

Post ID: 111wus
Title: 201210061504 → 2012-10-06 15:04 on A858's clock
Posted (UTC): 2012-10-06 19:04:21
Timezone: UTC−4 · title 15:04 against posted 19:04 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(A858DE45F56D9BC9201210061504) = 946fc6d11f3360fb7a8dafcf92a4b3d1 (name+title)
New here: Missing from the community archive; decrypted here for the first time. (new results)
GUIDs: 13
Filler GUID seed: new Random(267).Next(9) ✓ verified
Run: Run 35 (seed 854,622,578) (seed)
Draw: 321 · 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: 5 · 3
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: 848 hex characters = 424 bytes = 53 8-byte 3DES blocks.
Derive the key. Password = A858DE45F56D9BC9201210061504 (name+title). Key = MD5(password) = 946fc6d11f3360fb7a8dafcf92a4b3d1, 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 6b3ab32a-48b8-1334-932e-6ed7ebe969c0
  2 c79efccb-2668-1d6d-972f-f6f3b55a442b
  3 957e7e10-f926-380e-b2ae-91086ed3b783
  4 360616c6-3a1d-495d-bf2f-558ef20e159e
  5 212fc196-a2e8-6fba-98ca-57ed5c950e20
  6 2176a33a-b4c9-8c84-9c93-06e577585506
  7 d46d32e4-d14f-41f0-9cdc-09a625bbe8b0
  8 10487282-b413-354b-a1ba-84986c9aa2eb
  9 11f97e8e-f515-0a25-a56c-0aa0b9d81d02
 10 6dabb88c-67d6-6f93-bde2-23edfad732b8
 11 99fe4d4d-3960-826f-96d2-86dff8dc9617
 12 5df264a4-bce3-80b8-af69-7e09b159ede3
 13 06215815-cf77-14f7-a433-6bca13bca221

Explanation

Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 1134684306881. Exactly this sequence comes out of new Random(267).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 321 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