201207271422 x9npq
explained decrypted filler
3DES(name+name) ECB, 24 GUIDs, seed 0
From the post to its content
As posted (encrypted)
81389F9F5677133A 652C0477ECC0871D 96CF99893460A472 C82881C5E552F5B1 54E0AA56A9188136 1098FBDA762FEE62 36BDD540EAFF3C17 34D38F5C4303E4BA ED8BADE7F4202509 D27CD5725D4A589B 168C52F4CEDAC4F2 37DC3E49062A619C 583A453553A82C52 608A582A224534C2 03A643E4927E7214 6FA16625B514507B A2C5E3FA5AA5FC9A 811911CDC9735E1B CFBF48EE713A313C 51B95BC2F3AD6B5E D176085D5D796F75 DEA360AEDF246FCC D4422B27CBB085B2 D8EF92DC62B57971 6E804D475A913DBC 5F30831DE1B1024A 7D5FD629073F06BD D101AE6A65EAA99F 40055C4DB9092057 E782727FF472DADB 47EC4644A4AE7FE6 66A0F7E51A643A00 24156374D9AFB5BB 9C26265F1B00C126 6A34F93E64115A5B 004C7D592DEF424A 9F4AF2EA8A9C6CB2 225BB4F3028E0932 E077B767CC8048F1 F3F6D34B921E1A8A 5F2A730A2039AD92 84331D6B0F1E8EBE 8693C0500960DA88 B8452BA532909730 589237D6E60579C9 90446B1DB4ABBAF1 B14DC0EDEA611614 DA025BC65B628216 C34310512798FD32 AF81E6FBD0814EE3 151F611EFDC5FB8F 0DEFE69C80CC6AFE 639CD5842AED1A58 A9E6330B603F4ADC 04B99EB7A497D87A 7576CBCFC353201A 5C7D50F0FCFA26A3 E88C13F0CFDE579D E8E25B728028850C 7FD0408FEBD13CD5 DD2ED842DF27BDB6 2EE83D46D7D83219 BA6A8C47A76E3431 1481D0B932B73567 962D90F2DB607E42 F3A0F877ABA2988E 8B756DB176684AC6 BA4626D245B027C7 8CA48E9178E2E002 2278682D239C57A5 1D203E55F4E2B07B 85D75D47080E016B FE53A9AB84C20A7F 8CB045CB7FA9E773 50035472423357A3 194A0599BBB0062E 08543CD7D7139FBF 3AEA409EA3CEE484 B917FE880415A3E9 7C9E6DC75E81E60F 7917637A250A6179 773EE41D536C5E14 F8F195761295AFC9 CD375E1A8B03144B 292AB946D30B1A63 76B61772F1D3FB82 EEDF8566708FF7EB A59C26E6E9E88F24 5EB333F338315D6F B513FFF0C72F0EC1 F299B017154306B7 540ED64F0B6B0D3B 48C4230DB1747D50 C941C9E6311A2379 4BE04C0440F7DDE9 331FC3133279BC00 12ECFFDF2899BD4C
- Read the ciphertext. Strip whitespace: 1,552 hex characters = 776 bytes = 97 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 24 GUIDs as hex (shown below).
Decrypted: GUID list
1 930007c7-10e1-6dde-a1ac-821f6be0b23b 2 5da962a0-1e24-70c0-ba27-5a518335f868 3 fcfaf621-f455-62ae-aa29-51866b30f843 4 20071732-70a0-557b-8bde-9faca6e6405a 5 ee7cac77-8499-1549-a20c-5d3b69ff9276 6 e35b8923-6d59-5f63-86c0-4b097a9cc15c 7 598c6e20-3276-8338-a70a-a6389d4dbf6d 8 e8f5faea-72e5-380a-a3dc-907a76a7eb55 9 8f689a81-178e-8471-8804-f39a5bb437dd 10 dd645fc3-55bc-2b03-abca-af22bf3e9d4d 11 d706dbee-cd6e-2d3a-96c8-4c535863e6ac 12 8cc2f9e9-6de6-4be8-b455-f1bd6490460d 13 cc1efb54-d4de-508b-a5a8-fd23fa4f7ea7 14 c29c0286-f481-4800-abe3-6a3740c805fd 15 8b3c4c0c-5541-80ba-b124-31277a03eda0 16 c1a2c039-ffdd-05c6-8841-6f28e4c4dda1 17 5f56d23f-9558-70df-8b5d-dc83095d030b 18 4ac3c9b8-dace-8ea1-beed-d40a1d1b2a7e 19 197341e7-01bb-69df-998a-1bba66b5fb08 20 456b7ec3-cafa-235c-9250-c1849d39a56c 21 5ba4bae0-1aa8-70be-a63f-36444c855d9a 22 e61acea6-dc7a-7c99-b072-015a9e09c616 23 fc43a3db-8bd9-8bab-81bd-8c77cebd51ee 24 4c91011d-4403-06c2-a77c-aad8eac2f8d6
Explanation
- Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives
676515838224548078627780. Exactly this sequence comes out ofnew Random(0).Next(9): the per-post millisecond seed of the mask generator. The other 30 hex digits of each GUID areGuid.NewGuid()output and carry no message. - Explain the count. This post is draw 22 of Run 18 (seed 6,051,781):
new Random(6051781), Next(8,64) per post. The RNG predicts N = 24; the post has N = 24 ✓. The seed is the machine's uptime in ms when the app started (boot 2012-07-27 19:15–19:16). - Conclusion. Filler. The content is fully explained by the two RNGs.