Roundcube before 1.3.7 mishandles GnuPG MDC integrity-protection warnings, which makes it easier for attackers to obtain sensitive information, a related issue to CVE-2017-17688. This is associated with plugins/enigma/lib/enigma_driver_gnupg.php.

The OpenPGP specification allows a Cipher Feedback Mode (CFB) malleability-gadget attack that can indirectly lead to plaintext exfiltration, aka EFAIL. NOTE: third parties report that this is a problem in applications that mishandle the Modification Detection Code (MDC) feature or accept an obsolete packet type, not a problem in the OpenPGP specification