Multiple vulnerabilities were discovered in GnuPG, the GNU Privacy Guard:
The Elgamal decryption routine was susceptible to a side-channel attack discovered by researchers of Tel Aviv University. Ciphertext blinding was enabled to counteract it. Note that this may have a quite noticeable impact on Elgamal decryption performance.
The modular exponentiation routine mpi_powm() was susceptible to a side-channel attack caused by data-dependent timing variations when accessing its internal pre-computed table.
The keyring parsing code did not properly reject certain packet types not belonging in a keyring, which caused an access to memory already freed. This could allow remote attackers to cause a denial of service (crash) via crafted keyring files.
For the stable distribution (wheezy), these problems have been fixed in version 1.4.12-7+deb7u7.
For the upcoming stable distribution (jessie), these problems have been fixed in version 1.4.18-7.
For the unstable distribution (sid), these problems have been fixed in version 1.4.18-7.
We recommend that you upgrade your gnupg packages.