Several security issues were fixed in Libgcrypt.
Daniel Genkin, Lev Pachmanov, Itamar Pipman, and Eran Tromer discovered that Libgcrypt was susceptible to an attack via physical side channels. A local attacker could use this attack to possibly recover private keys. (CVE-2014-3591)
1 April 2015
A security issue affects these releases of Ubuntu and its derivatives:
Several security issues were fixed in Libgcrypt.
Daniel Genkin, Lev Pachmanov, Itamar Pipman, and Eran Tromer discovered that Libgcrypt was susceptible to an attack via physical side channels. A local attacker could use this attack to possibly recover private keys. (CVE-2014-3591)
Daniel Genkin, Adi Shamir, and Eran Tromer discovered that Libgcrypt was susceptible to an attack via physical side channels. A local attacker could use this attack to possibly recover private keys. (CVE-2015-0837)
The problem can be corrected by updating your system to the following package versions:
To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.
In general, a standard system update will make all the necessary changes.