201206271246 vo4x8
explained decrypted filler
3DES(name) ECB, 17 GUIDs, seed 431
From the post to its content
As posted (encrypted)
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
- Read the ciphertext. Strip whitespace: 1,104 hex characters = 552 bytes = 69 8-byte 3DES blocks.
- Derive the key. Password =
A858DE45F56D9BC9(name). Key = MD5(password) =34a14a42e98ff96095af56604e290cae, used as a two-key 3DES key. - Decrypt. 3DES-EDE2 in ECB mode, then strip the PKCS7 padding. The plaintext is 17 GUIDs as hex (shown below).
Decrypted: GUID list
1 01ade11d-4df7-80d4-8484-1bfdf618da5b 2 7c2ebe95-7d9e-2549-876e-999ed258a59e 3 fc3c2419-5397-0c8e-8b4f-16f05d4f8b9f 4 16e2ec41-7b59-4e26-8002-7ec62db8504f 5 ee8e0f08-b462-7bd9-b6bc-83e78bd0cdb4 6 8600b121-679f-1941-886d-05b0b3d87235 7 e4e90ae9-e781-0d51-a2b7-dcbe075f7938 8 c4c26441-f97e-6af6-b8dd-db79b80dd0b1 9 11480d6e-94aa-24af-b5f7-64aa1c60d5dc 10 d226b9d0-3e37-1638-ac42-53f9427ab244 11 fcbdc3f7-5d35-7723-b5fa-f26e88a8a8cc 12 5194e99b-995a-84df-837f-7e8169a236d3 13 12eeb9ea-302d-874d-8b0e-e93f257a4e3d 14 7e7a5b9c-f855-618b-ac1d-fc3146e15d36 15 cd586855-7007-6c85-99b8-64b98f28579c 16 fb1635c2-3247-19c1-8b7d-16615abe81bc 17 ba676bd4-fff9-0a66-be81-3798f3c84c75
Explanation
- Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives
82047106217886610. Exactly this sequence comes out ofnew Random(431).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 38 of Run 6 (seed 652,173,660):
new Random(652173660), Next(8,24) per post. The RNG predicts N = 17; the post has N = 17 ✓. The seed is the machine's uptime in ms when the app started (boot F 2012-05-15 19:06–19:16). - Conclusion. Filler. The content is fully explained by the two RNGs.