A858DE45F56D9BC9 archive

201208170643 ycc4u

explained decrypted filler

3DES(name+title) ECB, 26 GUIDs, seed 25

Metadata

Post ID
ycc4u
Title
201208170643 → 2012-08-17 06:43 on A858's clock
Posted (UTC)
2012-08-16 21:43:55
Timezone
UTC+9 · title 06:43 against posted 21:43 UTC
Author
[deleted]
Account
A858DE45F56D9BC9 main account
Subreddit
r/A858DE45F56D9BC9 the main subreddit
Category
F3 filler: 3DES(name/title) → GUID list, seed known
Size
1,680 hex characters · 840 bytes
Cipher
3DES-EDE2 (two-key Triple DES), ECB, PKCS7
Key
MD5(A858DE45F56D9BC9201208170643) = 6b50635c2fb78d66f252116f1e5aa636 (name+title)
New here
Missing from the community archive; decrypted here for the first time. (new results)
GUIDs
26
Filler GUID seed
new Random(25).Next(9) ✓ verified
Run
Run 24 (seed 39,416,093) (seed)
Draw
76 · predicted N = 26 ✓
Machine boot
2012-08-15 10:18–10:21 (seed = uptime at app start)
Sources
arctic-shift · body from arctic-shift
Links
Reddit · Arctic Shift · JSON
Score · comments
0 · 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: 1,680 hex characters = 840 bytes = 105 8-byte 3DES blocks.
  • Derive the key. Password = A858DE45F56D9BC9201208170643 (name+title). Key = MD5(password) = 6b50635c2fb78d66f252116f1e5aa636, used as a two-key 3DES key.
  • Decrypt. 3DES-EDE2 in ECB mode, then strip the PKCS7 padding. The plaintext is 26 GUIDs as hex (shown below).

Decrypted: GUID list

  1 64de4393-800f-7dea-9f4b-03ac0dcec163
  2 59bc7293-86a0-1e1a-95c3-8e767d898279
  3 8cec934d-7d38-2252-8798-20093b6edd49
  4 9beaacfc-5d03-85c9-8fe8-a1795cf09c2c
  5 01f97148-8c33-4b19-9be6-5044a195bb28
  6 4e1fc129-a9a3-3a37-85b3-addfcc9ed6a4
  7 bc14a7c8-f876-0caf-9540-ed37414da160
  8 503e687e-7615-8ad7-951d-bffbc88cf601
  9 659153e2-9bc0-0d36-94a6-84de22cefe9f
 10 22dba89c-bfc3-4841-a260-10a183530c63
 11 90925ba6-e1dc-6521-9bdc-c54491e9dd6f
 12 4b6d0763-97a1-8d8f-9a14-13b12ecf1070
 13 16e08526-c816-77c0-b8f9-c8cf1abf1059
 14 84b196d2-3dcb-4568-8f86-0062247bf49d
 15 434e37a7-9108-4ee3-8d9d-247eabb3ace8
 16 f57c7a03-723c-5b29-aa8e-771e2e011dfc
 17 4150e206-ac5c-3ca2-9b58-630c253ee5de
 18 f7e513d5-f6d4-4793-9d98-58664ba0ab53
 19 d763e931-aab9-3bb6-87ef-f60967f17b6a
 20 3ac80079-47fc-860a-90d9-ee38d5cef727
 21 948c9c1d-ed9f-1b3b-951a-e4793d364fcf
 22 c61c3bbe-163d-8fae-9c16-58e21561d927
 23 cf847689-113a-172c-803a-aeec00ab39ff
 24 8eef70e5-632e-674d-a5b0-0fde0d7a72e1
 25 c44329dd-8441-1ee3-b0a7-f567bcacfe73
 26 1d3e23f9-1d57-5b06-a8ac-8028dd1b22af

Explanation

  1. Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 71284308046874453438181615. Exactly this sequence comes out of new Random(25).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 76 of Run 24 (seed 39,416,093): new Random(39416093), Next(8,64) per post. The RNG predicts N = 26; the post has N = 26 ✓. The seed is the machine's uptime in ms when the app started (boot 2012-08-15 10:18–10:21).
  3. Conclusion. Filler. The content is fully explained by the two RNGs.

Related

Findings: Mask digit · Count RNG & runs · New results