A858DE45F56D9BC9 archive

201209201015 1062na

explained decrypted filler

seed 89

Metadata

Post ID
1062na
Title
201209201015 → 2012-09-20 10:15 on A858's clock
Posted (UTC)
2012-09-20 01:15:17
Timezone
UTC+9 · title 10:15 against posted 01:15 UTC
Author
[deleted]
Account
A858DE45F56D9BC9 main account
Subreddit
r/A858DE45F56D9BC9 the main subreddit
Category
F3 filler: 3DES(name/title) → GUID list, seed known
Size
1,744 hex characters · 872 bytes
Cipher
3DES-EDE2 (two-key Triple DES), ECB, PKCS7
Key
MD5(A858DE45F56D9BC9201209201015) = 972820ea84c0a489c0ec8663f3380a53 (name+title)
GUIDs
27
Filler GUID seed
new Random(89).Next(9) ✓ verified
Run
Run 32 (seed 945,377,703) (seed)
Draw
18 · predicted N = 27 ✓
Machine boot
2012-09-08 22:08–22:23 (seed = uptime at app start)
Sources
community-archive, arctic-shift · body from community-archive
Links
Reddit · Arctic Shift · JSON
Score · comments
10 · 0
Tags
automated (decryptable)2012Encrypted masked GUID listkey: name+titlerun: seed

From the post to its content

As posted (encrypted)

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
  • Read the ciphertext. Strip whitespace: 1,744 hex characters = 872 bytes = 109 8-byte 3DES blocks.
  • Derive the key. Password = A858DE45F56D9BC9201209201015 (name+title). Key = MD5(password) = 972820ea84c0a489c0ec8663f3380a53, used as a two-key 3DES key.
  • Decrypt. 3DES-EDE2 in ECB mode, then strip the PKCS7 padding. The plaintext is 27 GUIDs as hex (shown below).

Decrypted: GUID list

  1 ffa85c91-6aa8-118e-835b-505c6e8ccb8f
  2 7e80f26e-cec7-8c00-aa26-2a2cb0e01ec9
  3 250beda5-2acf-8e9f-b547-d1b4fc038040
  4 32b65b0a-afaf-4618-bd75-308bd29b1a58
  5 e1a2c7db-ecda-3254-912d-7efa30d6e138
  6 7b38c4d9-c01d-3806-9fed-95d4ffd57f76
  7 a0f5e6ae-d183-7184-982a-30225aacb874
  8 04976a1d-849c-0a0d-91c7-9f80eecbf341
  9 c9eac870-9191-8d50-89c3-1acab18313d3
 10 1b97d68b-70ac-0360-b7c0-478159fb94c5
 11 ce60a8b9-332c-7291-9cf3-7a0fc9e326f4
 12 da228ad5-28de-8de8-b454-e5520e812198
 13 6199c17d-db73-7efb-a993-557741136fd1
 14 a085d728-8d71-6c0f-aacd-d898506dffa5
 15 ab3998c5-958e-22b5-b659-336144bcf549
 16 f6903671-c417-520f-b3f0-834dacc876d2
 17 0d70b0a0-f940-2205-a429-e97750981ab8
 18 a6a20e51-b376-1397-a2c6-120a22019ff8
 19 7adba930-30df-0bba-b6c6-67dc43fe2ed7
 20 58c43f1e-2532-6fc3-abd2-3e867735ba64
 21 d938425f-8853-50df-912d-eef129e960ed
 22 a4e62631-c691-6a58-aab4-7d895e27fd1f
 23 8a7d20d9-8325-0fcf-9c23-5aaab14cfc5a
 24 359df7d6-cf3b-153a-84c2-87a545b16604
 25 a952133a-ab49-3a59-9e61-2babc351c71b
 26 27bf4d3e-d9d0-69a1-9537-693fa29e1e2f
 27 e39d899c-a76b-4881-845e-f5ef2bab70c9

Explanation

  1. Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 188433708078762521065601364. Exactly this sequence comes out of new Random(89).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.
  2. Explain the count. This post is draw 18 of Run 32 (seed 945,377,703): new Random(945377703), Next(8,64) per post. The RNG predicts N = 27; the post has N = 27 ✓. The seed is the machine's uptime in ms when the app started (boot 2012-09-08 22:08–22:23).
  3. Conclusion. Filler. The content is fully explained by the two RNGs.

Related

Findings: Mask digit · Count RNG & runs