Libgcrypt before 1.5.4, as used in GnuPG and other products, does not properly perform ciphertext normalization and ciphertext randomization, which makes it easier for physically proximate attackers to conduct key-extraction attacks by leveraging the ability to collect voltage data from exposed metal, a different vector than CVE-2013-4576.

Affected: Ubuntu:14.04:LTS: libgcrypt11

Daniel Genkin, Adi Shamir, and Eran Tromer discovered that Libgcrypt was susceptible to an adaptive chosen ciphertext attack via physical side channels. A local attacker could use this attack to possibly recover private keys.