A858DE45F56D9BC9 archive

201307240912 1ix6z4

explained decrypted filler

seed 679

Metadata

Post ID
1ix6z4
Title
201307240912 → 2013-07-24 09:12 on A858's clock
Posted (UTC)
2013-07-24 00:12:59
Timezone
UTC+9 · title 09:12 against posted 00:12 UTC
Author
[deleted]
Account
A858DE45F56D9BC9 main account
Subreddit
r/A858DE45F56D9BC9 the main subreddit
Category
F3 filler: 3DES(name/title) → GUID list, seed known
Size
2,064 hex characters · 1,032 bytes
Cipher
3DES-EDE2 (two-key Triple DES), ECB, PKCS7
Key
MD5(A858DE45F56D9BC9201307240912) = 851c804b24c43c6a61ee863ab4eca1ed (name+title)
GUIDs
32
Filler GUID seed
new Random(679).Next(9) ✓ verified
Run
Run 49 (seed 822,652,546) (seed)
Draw
95 · predicted N = 32 ✓
Machine boot
2013-07-10 11:27–11:29 (seed = uptime at app start)
Sources
community-archive, arctic-shift · body from community-archive
Links
Reddit · Arctic Shift · JSON
Score · comments
4 · 10
Tags
automated (decryptable)2013Encrypted masked GUID listkey: name+titlerun: seed

From the post to its content

As posted (encrypted)

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
  • Read the ciphertext. Strip whitespace: 2,064 hex characters = 1,032 bytes = 129 8-byte 3DES blocks.
  • Derive the key. Password = A858DE45F56D9BC9201307240912 (name+title). Key = MD5(password) = 851c804b24c43c6a61ee863ab4eca1ed, used as a two-key 3DES key.
  • Decrypt. 3DES-EDE2 in ECB mode, then strip the PKCS7 padding. The plaintext is 32 GUIDs as hex (shown below).

Decrypted: GUID list

  1 a91a6861-de2a-45bd-95db-85d5894e4543
  2 1e59b696-6f37-0fe1-afb4-adbb727b67a5
  3 4bac513c-db93-3e18-997a-a5e6c5daff14
  4 043d14a3-50b1-4a16-911c-ac77ff3a9eff
  5 6e9a2faa-8211-6702-8f31-f7b501426830
  6 98e4ac73-9145-8b69-9961-115fb5e23162
  7 2b050528-c0d7-1f56-bc48-53d41edb4433
  8 92ad96f9-1fab-073b-b1e3-225f7868b739
  9 cda19a27-f152-8e33-848e-cb86d8688b5c
 10 1e0b5e0b-9f0f-59ec-b01f-93db13ff190b
 11 3031f1de-371e-4455-b12a-02df07a306dc
 12 7af9896c-efe4-5c3b-91cf-625eea04f624
 13 0e57e445-25e6-36f9-a3de-20f238707708
 14 ad558ab3-ccaf-6061-8c32-33073b97cad9
 15 bb2cccd3-777b-2582-a1f8-a6e7514b69d6
 16 96b8f9ca-b577-0539-8eaa-5dae2a9bf8cd
 17 b94f86a1-358c-297d-8c1f-2482399fb1f6
 18 f766fc94-9e4a-858f-861e-86a57ea642dd
 19 6a1ff4de-7ece-079e-838d-ea96ea7bb3f2
 20 1b83bb11-210b-216b-bedf-268e8df96921
 21 06d92428-b309-03b9-a276-76b1c13f49f7
 22 b9817a7b-2608-3705-afb7-fd510dd92637
 23 d539f656-0ac9-6c23-8009-747ec118fb8b
 24 02a5ebf8-e31f-23ec-92a7-d38069b9a367
 25 664cdfc2-a9b9-2b61-87c8-29286231cbb4
 26 55d72684-e604-222f-8a40-2104b31908ea
 27 e119a0fd-044c-6666-87aa-aa24b5fba007
 28 bd07f2f7-2104-3b29-b3ef-b82b483d1952
 29 fb5a506c-5d84-0f38-b5c9-8c1ebdd5e02e
 30 5703e2db-1d4a-8fb5-b585-07f9eba692bb
 31 5db527fa-a6a8-7893-bf22-429ba8ad19ac
 32 e9c2876a-d5f3-22f9-9bc6-8c0589465698

Explanation

  1. Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 40346810854536202802036222630872. Exactly this sequence comes out of new Random(679).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 95 of Run 49 (seed 822,652,546): new Random(822652546), 4·Next(8,16) per post. The RNG predicts N = 32; the post has N = 32 ✓. The seed is the machine's uptime in ms when the app started (boot 2013-07-10 11:27–11:29).
  3. Conclusion. Filler. The content is fully explained by the two RNGs.

Related

Findings: Mask digit · Count RNG & runs