CVE-2018-20187

A side-channel issue was discovered in Botan before 2.9.0. An attacker
capable of precisely measuring the time taken for ECC key generation may be
able to derive information about the high bits of the secret key, as the
function to derive the public point from the secret scalar uses an
unblinded Montgomery ladder whose loop iteration count depends on the
bitlength of the secret. This issue affects only key generation, not ECDSA
signatures or ECDH key agreement.

Bugs

• <http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=918732&gt;