Red Hat Security Advisory 2013-1458-01 – The GNU Privacy Guard is a tool for encrypting data and creating digital signatures, compliant with the proposed OpenPGP Internet standard and the S/MIME standard. It was found that GnuPG was vulnerable to the Yarom/Falkner flush+reload cache side-channel attack on the RSA secret exponent. An attacker able to execute a process on the logical CPU that shared the L3 cache with the GnuPG process could possibly use this flaw to obtain portions of the RSA secret key…. Red Hat Security Advisory 2013-1458-01 – The GNU Privacy Guard is a tool for encrypting data and creating digital signatures, compliant with the proposed OpenPGP Internet standard and the S/MIME standard. It was found that GnuPG was vulnerable to the Yarom/Falkner flush+reload cache side-channel attack on the RSA secret exponent. An attacker able to execute a process on the logical CPU that shared the L3 cache with the GnuPG process could possibly use this flaw to obtain portions of the RSA secret key.

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