The vulnerability in openssl_encrypt (pip) versions <= 1.4.7 involves the 'hsm fido2-test' and 'hsm onlykey-test' diagnostic commands unconditionally printing the full derived hardware pepper as hex to stdout/stderr (in crypt_cli.py, handle_hsm_command). This information exposure can lead to sensitive data being recorded in terminal scrollback, session recordings, or continuous integration logs. However, the leaked pepper is derived from a random per-invocation test salt and is salt-bound, so it cannot be used to decrypt actual encrypted files. Additionally, a related plugin issue logged raw prf_data outside the secret-redaction path. The vulnerability was addressed in versions 1.4.8 and 1.5.0 by removing the hex dumps and ensuring plugin debug output is routed through the redaction layer.

Sensitive derived hardware pepper values are exposed in logs and terminal output, potentially leaking information that could be used to infer internal states during diagnostic tests. However, the leaked values are bound to random test salts and cannot be used to decrypt real encrypted data, limiting the practical impact. There are no known exploits in the wild.

Upgrade to openssl_encrypt versions 1.4.8 or later, where the vulnerability is fixed by removing the hex dumps and routing debug output through a redaction layer. Since no official patch links or advisories are provided, verify the upgrade path with the vendor or trusted package repositories. Avoid using affected versions (<=1.4.7) in sensitive environments until patched.