201210260123 123zns

explained decrypted filler

3DES(name+title) ECB, 21 GUIDs, seed 727

Metadata

Post ID: 123zns
Title: 201210260123 → 2012-10-26 01:23 on A858's clock
Posted (UTC): 2012-10-26 05:23:41
Timezone: UTC−4 · title 01:23 against posted 05:23 UTC
Author: [deleted]
Account: A858DE45F56D9BC9 main account
Subreddit: r/A858DE45F56D9BC9 the main subreddit
Category: F3 filler: 3DES(name/title) → GUID list, seed known
Size: 1,360 hex characters · 680 bytes
Cipher: 3DES-EDE2 (two-key Triple DES), ECB, PKCS7
Key: MD5(A858DE45F56D9BC9201210260123) = 5e681d58dc2780ed33d944bdae540775 (name+title)
New here: Missing from the community archive; decrypted here for the first time. (new results)
GUIDs: 21
Filler GUID seed: new Random(727).Next(9) ✓ verified
Run: Run 38 (seed 1,045,884,937) (seed)
Draw: 55 · predicted N = 21 ✓
Machine boot: 2012-10-11 03:41–03:51 (seed = uptime at app start)
Sources: arctic-shift · body from arctic-shift
Links: Reddit · Arctic Shift · JSON
Score · comments: 1 · 0
Tags: automated (decryptable)2012Encrypted masked GUID listarctic-onlykey: name+titlerun: seed

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 = A858DE45F56D9BC9201210260123 (name+title). Key = MD5(password) = 5e681d58dc2780ed33d944bdae540775, 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 6cedbc4f-fa0d-4fb2-9099-a4ea8a0a9bb6
  2 08491e33-70d0-175c-acee-8f510ddbcead
  3 6e797e05-78d0-8522-ad20-49d7d3fa3231
  4 f8564c00-2e9a-6c66-8a10-20ef3023f49e
  5 563b24f9-3f91-3325-bfaa-29defd0a33ff
  6 16feb8ac-3b3e-7993-b087-f9122ebf2d01
  7 c005b6b9-6c26-50b2-9689-935112577262
  8 e803b28b-6fb6-1785-a738-38a4efd60abc
  9 5f9b3201-6050-87de-8d27-0e2ff0dc50a3
 10 33b787fd-2a98-305c-8f57-8c97cfcc4c0d
 11 5724788a-38dd-8b80-ae76-9cb27f7e6d8f
 12 0a40b4f8-4f99-0c75-8b6c-237d210f09f6
 13 5b5c0a73-0707-3b49-92ed-0cf95224ad56
 14 2dbdb4d0-b8ca-6aaf-9a2a-8756b69a0ccc
 15 846dda75-b2a8-7760-aff8-c244cb5066b2
 16 7b7f736d-eb93-006e-9a87-219b9a3d35fc
 17 a9bdd82b-e593-4605-b506-23e5ee894781
 18 61437ad6-1142-682b-a83a-170fe445c024
 19 013beae4-9780-336c-ae8b-f831dbf35917
 20 5c8a00e9-0d62-720b-b9c2-fab6a30f878f
 21 c78d24b4-8d05-305d-8acc-13c68eddc4be

Explanation

Explain the mask digits. The version nibble (13th hex digit) of each GUID, read in order, gives 418637518380367046373. Exactly this sequence comes out of new Random(727).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.
Explain the count. This post is draw 55 of Run 38 (seed 1,045,884,937): new Random(1045884937), Next(8,64) 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 2012-10-11 03:41–03:51).
Conclusion. Filler. The content is fully explained by the two RNGs.

Metadata

From the post to its content

As posted (encrypted)

Decrypted: GUID list

Explanation

Related