A858DE45F56D9BC9 archive

201303041620 19ntnv

explained decrypted filler

seed 728

Metadata

Post ID
19ntnv
Title
201303041620 → 2013-03-04 16:20 on A858's clock
Posted (UTC)
2013-03-04 21:20:51
Timezone
UTC−5 · title 16:20 against posted 21:20 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(A858DE45F56D9BC9201303041620) = ddf9d6d0f36666c41066f842b2efe0bf (name+title)
GUIDs
32
Filler GUID seed
new Random(728).Next(9) ✓ verified
Run
Run 42 (seed 983,934,859) (seed)
Draw
176 · predicted N = 32 ✓
Machine boot
2013-02-13 10:26–11:32 (seed = uptime at app start)
Sources
community-archive, arctic-shift · body from community-archive
Links
Reddit · Arctic Shift · JSON
Score · comments
2 · 1
Tags
automated (decryptable)2013Encrypted masked GUID listkey: name+titlerun: seed

From the post to its content

As posted (encrypted)

904D08EC14EE2720 5948F1CBC4BAC579 BD52ADFD50903B27 AA3F27F5D84E6A9A CCB50F9C1A983785 F345DE6EE2CB4284 165C8A6CEA57C7A1 7D29585FA834B41D E18810F45A8B3335 896AD21ED190C254 66ECBF94D8BFC336 5B17B7122F8CDE5F 8E874AA429C79710 F81C40AE94A34EA4 B3D4E6D24FFDC5DD A4551918389F4B1F 96FFA2B4849FEBED 2C5F77211DE30985 92BB3002AFB7781B 329C7A825AC25A64 EEA5380772C6A4AB E8B65B0BDEEBC891 1DC605EF7C17F0DB 622B34123A01BFD6 FFBB767AD9CBFD05 D46B1571FD325B9B C88DABCC3D86DDB0 203B901661C85211 34D717217329834F 86008DE43A3072DF 33BBADEC082BE463 0C6B74C602342CAC C50E0078FFE876E9 522F02FA49AE1074 6F74A36CE8831123 05A470171F2334A3 827F5CF4131FA841 2D3BA029C058B818 7554E3DA552D533C D95E72CCF00BFCF2 483D9B1056E7673D 0704752216DAE515 F39BC9A313761D67 2C4543F67CA11700 352C385822C4976F EBF3517CF70B20FF 1ADF3C960390BB5C EF38444305AA28EB A3D28A70609FB7FE A6C8F1EBC0BFE898 7A6FE0BC6D24BDA1 BA7F12456D1AE8DE D8269C11A52D2475 55D23F574211F3F5 CE7E80A9BA3DE415 86AD410FB292108B B8321A9682DE94CA A3E2CB059EC7F9FA 62AEED3ECE3CCE86 162BDF9D9C85D60A 66369E25BE61A752 16C01B154A5C2068 B168D9B47C6816A2 C7CFA3203F10EAB4 62A225F8F49D3CD7 996336B61FD3C3F2 8118A3298ED9F747 B86A73AD8A26EE72 FBF4DB1652C45508 287D4A0C4D6D7469 9101CBD2C74447F5 F77A8CF45245E068 17B746F9B389B461 76E5D4F60B07F119 3025E539115E1708 7769DD8C2E6B89C5 150CAE332D47AC22 3673520FF5A92234 434BC9AA1D6481C2 1290F07C34967FFD 77E4BD87DBF7BDA2 F6778BD52BFA37D8 C72056F0881AE07E 7D406C6B7BF30CBD C2EFC202531ADCCA 9311399F75EA9ECA 5391127565E813F8 157ED68913E84BBC 33EBC0FEA429346D 26824086F190030A 9521650CD9B28FEB A3F0E16FB75D2767 0C842238505E14AE 1223100E084CA721 119D4A13A42F557E 8EB7EED7C1AE406D A7C2E17FC071C663 77893C78DCD9F93A B8EFF11AB51B19A5 2BC567EF14AB83E6 57FA965596BA3F34 FE76B8D300BDAFE4 E3D0EA444F6B43A9 669E4DE4D62ECCD3 35DF97B539905150 CFF150109B6F4320 5D546346EEC3BBCA 75042FA9BEAE5A91 E50EE4FB612251EC 53B86D4AF3906BEA 626BF99310598E00 A470FDCD85510463 49157389295E31B6 3EFCC5D2C609FF1E 1EB267B35CEB7060 CA7EB7D44872A32B 269AEAA6CF07378E 160413FC230C66B0 3B29B06911C68F71 563828DD1817D184 EA0B544C26C515FB D7D2D58C2C959A27 92B9A1A35F0DBACA 927288523BA97CEC 11C58FC36C76A1AE 2FD370438FC2C8B8 18DA7EE54442F01F D1EC9C228A1E3E6A 4EEAC4845AA87EEB
  • Read the ciphertext. Strip whitespace: 2,064 hex characters = 1,032 bytes = 129 8-byte 3DES blocks.
  • Derive the key. Password = A858DE45F56D9BC9201303041620 (name+title). Key = MD5(password) = ddf9d6d0f36666c41066f842b2efe0bf, 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 81cc7a51-1798-03f8-84bb-983d4b248e21
  2 2fb92f59-e1f3-3b19-b897-4f6839c1c7a3
  3 092e08ab-b4d6-5eaa-b3a5-adf34067a7f0
  4 5fa3a098-113b-8349-9675-78925e8a8488
  5 2bcc2fc3-5ba7-722e-8c0f-686e15c19360
  6 0cd5f742-312b-6e64-b74c-1dcf61f0a9d8
  7 e60ecce7-522b-03ed-bde6-2f73c5de5e70
  8 71a6d56b-2992-6f96-8119-f45a03cb8452
  9 68c23eee-24aa-08f5-92be-d8beef73069c
 10 f8c4cd23-3580-695d-870d-7db10c29ace8
 11 f82268d1-a885-535c-b11b-733db7c5c744
 12 345a0ef5-a2e5-79f2-bc11-523cf048244b
 13 4c261c0a-b2ff-0017-88dc-a83185d7ede2
 14 cddd5718-ad89-1c91-b9cc-2f779d4d177b
 15 8e3aeff9-a95b-59e9-b72b-2bdcb491149d
 16 78511408-a82e-6d71-9f93-90dc92f40f4e
 17 d48427eb-6c40-7701-9d78-7884c080158f
 18 890a24df-e203-303a-a081-0e5d2383c260
 19 5903120f-50f2-339e-a2ab-ca40f7fda8e4
 20 a17ee7f1-991f-1d76-8d17-bb17d8681aba
 21 e5ee94b4-8cae-4a99-bce0-a85c48b9e3f2
 22 08008b79-2b47-4916-a144-c0e3d46d469a
 23 cc4a98c2-fe75-0dc0-afff-200d8a1aff6e
 24 718a471a-4fbe-3c4f-a1fe-d2be080d7b06
 25 6764fdd4-3f64-0b27-8912-71b08cdd918b
 26 fef081f4-5300-631a-a063-895b1c7a6119
 27 aa85f2fe-3d6d-79a6-ae4a-c411e22b658a
 28 38989bcc-80ce-61db-b667-7bdf3d0601ec
 29 daddf2ff-3069-594d-a228-e973a5206850
 30 75af4833-dde7-30d6-8c17-5885615fbad2
 31 d39321fa-835c-8cbd-821d-da21ca4639e7
 32 dc22daf8-5b26-1bd1-ad8b-f2ab32899257

Explanation

  1. Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 03587606065701567331440306765381. Exactly this sequence comes out of new Random(728).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 176 of Run 42 (seed 983,934,859): new Random(983934859), 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 2013-02-13 10:26–11:32).
  3. Conclusion. Filler. The content is fully explained by the two RNGs.

Related

Findings: Mask digit · Count RNG & runs