ExpressKeys vs KeePassXC Comparison

White-box design and cryptographic-trust-assumption review plus dynamic penetration testing and source-code audit of the ExpressKeys Android and iOS apps and their shared Rust core. Five senior testers, sixteen days. Backend components and third-party dependency analysis were out of scope.

First-level security certification of KeePassXC 2.7.9 on Windows — full source-code review, penetration testing of every security function, and cryptographic and random-number-generator analysis

The vault is protected by a symmetric document key, itself wrapped by a root key derived from your vault password via PBKDF2-HMAC-SHA512 at 210,000 iterations. Cure53's March 2026 audit flagged this as GPU-crackable and recommended a memory-hard function (Argon2id or scrypt) instead.

The database is encrypted with AES-256 by default (Twofish and ChaCha20 are also selectable) in the KDBX 4 format, with an HMAC-SHA-256 integrity check that detects tampering. The master key is derived with Argon2d by default — a memory-hard function that resists GPU and ASIC cracking — with the older AES-KDF still available. The composite master key can combine a password, a key file, and a YubiKey or OnlyKey challenge-response secret.

ExpressVPN (and ExpressKeys as one of its products) is registered in the British Virgin Islands and has been part of Kape Technologies plc (LSE-listed, ultimate beneficial owner Teddy Sagi) since September 2021.

Volunteer, community-run open-source project under the keepassxreboot organization on GitHub — no company and no venture funding behind it. Development is paid for by donations. Forked from KeePassX in 2016; the KeePass lineage goes back to 2003.