Search resumed: unusual storage and persona-preservation explanations under investigation. The captured bytes have not identified the small-record cipher or yielded authenticated plaintext. Writer code, a provenance-linked format specification or an authorized key would enable further cryptographic work. Read the completed comparison with earlier writing and similar systems.
The large uploads strongly match Fernet. The small xz records do not. They may belong to the same publishing workflow while storing different kinds of objects through different encodings or encryption formats.
Base64 decoding reveals the container. It does not decrypt its contents. Standard Fernet combines AES-128-CBC with HMAC-SHA256; its 32-byte key splits into two 16-byte keys. It is not AES-256 merely because that combined key is 32 bytes. Fernet specification.
All nine objects fit the expected layout. Their IV fields are distinct, and no 16-byte ciphertext block repeats across 77,644 blocks. We have not verified the keyed authentication fields, identified the producing library or recovered plaintext.
Assuming standard Fernet padding, these are the possible input lengths in bytes. The encrypted input could already be compressed or serialized.
| Group | Ciphertext bytes | Conditional plaintext bytes |
|---|---|---|
| xinzhai | 64,928 | 64,912–64,927 |
| xinzhai_v5.2 | 65,488 | 65,472–65,487 |
| xinzhai_v52 | 99,680 | 99,664–99,679 |
| xinzhai_v60 | 113,552 | 113,536–113,551 |
| xinzhai_v61 | 125,296 | 125,280–125,295 |
| xinzhai_v70 | 151,504 | 151,488–151,503 |
| xinzhai_v71 | 180,784 | 180,768–180,783 |
| xinzhai_v72 | 209,904 | 209,888–209,903 |
| xinzhai_v73 | 231,168 | 231,152–231,167 |
Padded CBC ciphertext comes in 16-byte blocks. With one fixed-size wrapper, every record length would leave the same remainder when divided by 16.
The knowledge lengths leave six different remainders; the plans leave two. This rules out that single fixed-wrapper, padded-CBC model. None has the length required for a full binary Fernet token.
A hypothetical 12-byte nonce plus 16-byte authentication tag would leave 65–400 bytes of knowledge plaintext and 618–619 bytes of plan plaintext. AES-GCM and ChaCha20-Poly1305 could both fit that arithmetic. We have not established such a wrapper or identified its nonce or tag. AEAD documentation.
No literal fragment relationship was found. All 1,193,931 eight-byte windows in the 3,495 small records are unique, and none appears anywhere in the nine decoded large objects. The small records therefore are not copied byte ranges of those captured objects. Related plaintext encrypted separately remains possible. Read the overlap audit.
Controlled synthetic examples reproduced all 12 small-record lengths with both AES-128-GCM and ChaCha20-Poly1305. This confirms that the sizes alone cannot identify AES. No captured ciphertext was decrypted. Read the controlled comparison.
A further whole-record check found no second Base64 layer and recovered no complete gzip, zlib, bzip2 or XZ stream. One zlib-header candidate requests an unavailable preset dictionary and remains unresolved. Read the wrapper check and limits.
New search round: unusual explanations and concrete leads →
A large-object uploader alongside a periodic small-record writer remains a plausible interpretation of the interleaved posts. The cryptography does not tell us whether the objects are agent code, memory, documents, backups or something else. Distinct ciphertext does not prove distinct plaintext, a fresh nonce, different keys or a swarm.
The missing discriminator is the writer implementation or an authorized key. More Base64 decoding will not supply either.
Full audit and exact length reasoning · Comparison with the supplied archive
Updated September 5, 2026. All 3,574 source bodies were checked against the fixed survey. No payload bytes or keys are published here; no decryption was performed.