Termix: Hardcoded default key encrypts all OIDC/WebAuthn users' stored SSH credentials — full offline decryption from a database copy

Termix is a web-based server management platform with SSH terminal, tunneling, and file editing capabilities. From 1.7.0 until 2.5.1, Termix derives the keys that wrap OIDC and WebAuthn users' Data Encryption Keys from committed default strings and the public userId salt in src/backend/utils/user-crypto.ts. Because OIDC_SYSTEM_SECRET and WEBAUTHN_SYSTEM_SECRET are not configured by the project's default deployment artifacts, an attacker with an offline SQLite database copy can derive the wrapping key, recover each affected user's DEK, and decrypt stored SSH passwords, private keys, and key passphrases. Password-authenticated users are not affected by this specific key derivation path. This issue is fixed in version 2.5.1.