A858DE45F56D9BC9 archive

201207100244 wa38g

explained decrypted filler

seed 290

Metadata

Post ID
wa38g
Title
201207100244 → 2012-07-10 02:44 on A858's clock
Posted (UTC)
2012-07-09 17:42:10
Timezone
UTC+9 · title 02:44 against posted 17:42 UTC
Author
[deleted]
Account
A858DE45F56D9BC9 main account
Subreddit
r/A858DE45F56D9BC9 the main subreddit
Category
F3 filler: 3DES(name/title) → GUID list, seed known
Size
1,936 hex characters · 968 bytes
Cipher
3DES-EDE2 (two-key Triple DES), ECB, PKCS7
Key
MD5(A858DE45F56D9BC9A858DE45F56D9BC9) = 0dcc4bd9e114ebc42078977dc9125404 (name+name)
GUIDs
30
Filler GUID seed
new Random(290).Next(9) ✓ verified
Run
Run 15 (seed 117,733,640) (seed)
Draw
15 · predicted N = 30 ✓
Machine boot
2012-07-06 08:59–12:59 (seed = uptime at app start)
Sources
community-archive, arctic-shift · body from community-archive
Links
Reddit · Arctic Shift · JSON
Score · comments
9 · 2
Tags
automated (decryptable)2012Encrypted masked GUID listkey: name+namerun: seed

From the post to its content

As posted (encrypted)

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
  • Read the ciphertext. Strip whitespace: 1,936 hex characters = 968 bytes = 121 8-byte 3DES blocks.
  • Derive the key. Password = A858DE45F56D9BC9A858DE45F56D9BC9 (name+name). Key = MD5(password) = 0dcc4bd9e114ebc42078977dc9125404, used as a two-key 3DES key.
  • Decrypt. 3DES-EDE2 in ECB mode, then strip the PKCS7 padding. The plaintext is 30 GUIDs as hex (shown below).

Decrypted: GUID list

  1 c9af5d1f-fa1c-2099-b431-0f8dee34e274
  2 c3363910-9628-8ac5-a879-219ff8f9fb97
  3 b63bc294-4aa3-4a74-96e8-b2fb8034e66c
  4 0324fc75-d4d4-4d46-9198-8fc00921dd1c
  5 380d11d0-ebed-19b3-86b4-f3474a31c67b
  6 aebfff19-3293-8eb2-a308-5ae73afdabab
  7 38143f00-d17e-7d20-a960-e9cfdd059a5a
  8 19a75692-8a5d-8b14-8783-b30051aa5b2a
  9 d7f00e61-a565-7857-97f4-9fd8634b14ee
 10 e0c5c211-3ef1-173a-a60a-ce0f1b8e9e19
 11 c35fb506-b7f9-882d-93d2-f4b3f62f6ea5
 12 31e8348e-23d0-7fea-a34a-f54dbdd072cb
 13 9eb09c0d-9c54-80bc-8099-166057e9f7ea
 14 39808bdf-aa1c-303e-ad25-e388bfc422b9
 15 5ea74966-91c9-8276-bc40-7411b35ce5b4
 16 35490593-1d08-15dc-8d17-28ac19ff9c37
 17 59d57059-5248-6188-9520-c3d5246af814
 18 3a4886cc-cbdb-7fe1-98f6-6ea191d33a61
 19 5576ad09-9e51-4064-907f-50dbbf7363b9
 20 012174cf-6a40-5176-8522-a355c447c627
 21 94086ec8-df6a-351a-b963-ec51878d94cf
 22 4657a98d-48b8-82a2-a8ef-ea21125f3784
 23 bf07b466-594f-0b4a-bf43-336345c47477
 24 8f57b1b8-ce5b-328e-8785-1ed1331473fd
 25 79e3c7a1-b3ac-1362-9741-290f2e4c5723
 26 b03541d7-bb40-070a-b4a5-f9fb3e28ee72
 27 80f2ec96-450e-2e79-b630-61f6b80a2e08
 28 34be1fc0-5ae0-331c-9ac6-440af73ec9e0
 29 7cdf27cb-2139-5c72-a237-16440621d2a2
 30 050230bc-7a38-549a-8cdc-ad4c149b7f91

Explanation

  1. Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 284418787187838167453803102355. Exactly this sequence comes out of new Random(290).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 15 of Run 15 (seed 117,733,640): new Random(117733640), Next(8,64) per post. The RNG predicts N = 30; the post has N = 30 ✓. The seed is the machine's uptime in ms when the app started (boot 2012-07-06 08:59–12:59).
  3. Conclusion. Filler. The content is fully explained by the two RNGs.

Related

Findings: Mask digit · Count RNG & runs