Security Notes

HVCE v4 includes password-based authenticated encryption, but it is a reference implementation, not a professionally audited security product.

Password mode

The archive encrypts the private manifest and payload together. File names and directory structure are not visible without the password.

Primitive stack:

PBKDF2-HMAC-SHA256 -> 64 bytes
32-byte key 1 -> ChaCha20 stream encryption
32-byte key 2 -> HMAC-SHA256 authentication

Default KDF iterations: 300000.

Use:

python hvce.py compress folder secure.hvce --ask-password --recovery-percent 10
python hvce.py extract secure.hvce restored --ask-password

Why symmetric-only is used

The v4 “post-quantum” security stance avoids RSA/ECC public-key wrapping in the archive format. Symmetric 256-bit keys retain a large margin against generic quantum search, assuming strong passwords and sufficient KDF work.

Threat model

Provides:

confidentiality against attackers without the password;
filename and metadata privacy when encrypted;
tamper detection before decryption;
extraction verification with SHA-256;
recovery against limited storage corruption when recovery records are present.

Does not provide:

protection from weak passwords;
protection from malware on the machine that captures passwords;
deniable encryption;
independently audited cryptographic assurance;
legal/compliance certification.

Recommended use

For important personal archives, use:

python hvce.py compress input output.secure.hvce --profile balanced --ask-password --recovery-percent 10

Keep at least one external backup. Recovery records are not a substitute for backups.