201206271805 voegg
explained decrypted filler
3DES(name) ECB, 18 GUIDs, seed 38
From the post to its content
As posted (encrypted)
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
- Read the ciphertext. Strip whitespace: 1,168 hex characters = 584 bytes = 73 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 18 GUIDs as hex (shown below).
Decrypted: GUID list
1 453d4093-2bcc-5736-b259-cc95d4197ee7 2 7a8f6861-b388-89a3-8cb5-6ee692657ba8 3 8be994c4-b311-23fd-937d-dbf71330fc96 4 b9692be5-8314-6041-91e4-1296debd5f40 5 fdda4652-f3aa-3ce3-8425-563803f44e13 6 cf59709c-40c2-69a0-83f0-0853dc8f0157 7 b42cf2a5-ada3-8be1-8918-3a355227bfb6 8 e0fccb1e-c43f-4faf-a1bf-500b30cadc11 9 b416f91d-98d1-6ac4-8e28-66120fd81310 10 4960401a-4c48-2872-ae89-b953f790e284 11 77cb28bf-cf9f-205f-a764-f032a493ee50 12 95dc8ca6-13c5-1530-8c33-b0fa2cdd7abe 13 41b35ba9-55bd-6073-b57b-c3c5ec48c652 14 7810ec7c-b2c6-2e93-b7e5-a6c90004f473 15 23673685-bddc-5ce2-86fc-505d4004787a 16 698a8312-f378-6693-8c18-49c8a25933b2 17 f4804569-7c4e-7d8b-925a-d414335dc55d 18 7cb5ea48-0460-4110-b511-07637995952e
Explanation
- Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives
582636846221625674. Exactly this sequence comes out ofnew Random(38).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 6 of Run 7 (seed 629,367,141):
new Random(629367141), Next(8,24) per post. The RNG predicts N = 18; the post has N = 18 ✓. The seed is the machine's uptime in ms when the app started (boot F 2012-05-15 18:57–19:13). - Conclusion. Filler. The content is fully explained by the two RNGs.