201206270955 vnv6c
explained decrypted filler
3DES(name) ECB, 21 GUIDs, seed 344
From the post to its content
As posted (encrypted)
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
- Read the ciphertext. Strip whitespace: 1,360 hex characters = 680 bytes = 85 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 21 GUIDs as hex (shown below).
Decrypted: GUID list
1 b3c9a005-b555-3392-8e16-13f21d777eaf 2 d086f915-0ccd-68c1-a6df-ce2d416ed7dd 3 3d02cd72-1e90-1f0f-8b35-0dbdae4d8b7d 4 b574f249-c191-8067-8572-82f7b41b6891 5 975fc457-52ca-46c2-a794-59b059663d9c 6 f69c121e-2d91-18a3-af63-ea7cfeeebbb5 7 8ca565aa-0c40-09d5-a6fe-ed48a425bd1c 8 ae23bcb7-e283-033c-a0d1-cdb9ea246d1b 9 f0514fc0-934b-4123-934f-dda4406bd2e0 10 aea0be92-ffcb-1cb3-a2de-1fff1aec2a36 11 98cd0024-ecd9-6bbe-baeb-0f148e4a0233 12 25ed1a27-2b3a-084d-bba8-8f0fb0c864c0 13 b9df7f77-f36a-1a62-8c4e-5d75e810ad3c 14 b2675f27-3c07-3bd5-a7fe-c4273041d17a 15 0c89abf3-c09f-600f-8271-b1e01af5f448 16 d902be07-9db5-71ca-b2c6-f02ef62fd47e 17 62b4acf2-c987-46b6-a370-d4828cef0507 18 80480203-b028-2053-a7bb-5b301fbf13dd 19 45b894a2-d02b-874f-ab5f-92a44942b4a6 20 36752c93-1347-4580-9b82-08c9c2959490 21 fcc3a177-3a60-49b3-9354-392fefafae5e
Explanation
- Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives
361841004160136742844. Exactly this sequence comes out ofnew Random(344).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 21 of Run 6 (seed 652,173,660):
new Random(652173660), Next(8,24) per post. The RNG predicts N = 21; the post has N = 21 ✓. 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.