Executive brief
openssl_encrypt is a tool for encrypting and decrypting files using password-based encryption with support for post-quantum cryptography. Versions before 1.4.9 fail to validate whether embedded post-quantum private keys are properly encrypted, allowing attackers to craft malicious files that decrypt under any password and falsely claim to be integrity-verified. This bypasses the authentication mechanism entirely, potentially allowing attackers to distribute trojan files that users will unknowingly accept as legitimate.
Technical details
The vulnerability is an improper authentication flaw (CWE-287) in the decrypt_file function. The vulnerable code trusts unencrypted embedded post-quantum private keys in file metadata when the pqc_key_encrypted field is absent or false; for mayo/cross/ML-KEM hybrid algorithms, decryption derives the bulk key only from this embedded key, completely bypassing password verification. An attacker can craft a v5-format file with a raw attacker-controlled post-quantum private key, set aead_binding to false, and pre-compute content hashes, resulting in a file that decrypts under any password while displaying "integrity verified". The vulnerability requires no network access and affects versions before 1.4.9. The fix (released in 1.4.9) default-denies any file with an unencrypted embedded PQC private key before any decryption occurs; legitimate legacy files can be read by explicitly passing allow_unencrypted_pqc_key=True.
Affected products
- jahlives openssl_encrypt before 1.4.9
Timeline
- 2026-08-27: disclosed
- 2026-08-27: patched: Version 1.4.9 released