CVE-2018-6829

cipher/elgamal.c in Libgcrypt through 1.8.2, when used to encrypt messages directly, improperly encodes plaintexts, which allows attackers to obtain sensitive information by reading ciphertext data (i.e., it does not have semantic security in face of a ciphertext-only attack). The Decisional Diffie-Hellman (DDH) assumption does not hold for Libgcrypt's ElGamal implementation.

This is not a security flaw in libgcrypt. However if an application uses The El-gamal algorithm implemented by libgcrypt in a particular way than the application would be vulnerable to security flaw(s). More detailed explanation is available at: https://lists.gnupg.org/pipermail/gcrypt-devel/2018-February/004401.html

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.