nCipher HSM before 2.22.6, when generating a Diffie-Hellman public/private key pair without any specified DiscreteLogGroup parameters, chooses random parameters that could allow an attacker to crack the private key in significantly less time than a brute force attack.
https://exchange.xforce.ibmcloud.com/vulnerabilities/25060
http://www.vupen.com/english/advisories/2006/0862
http://www.securityfocus.com/bid/17006
http://www.securityfocus.com/archive/1/427146/100/0/threaded
http://www.ncipher.com/resources/95/sa12_insecure_generation_of_diffiehellman_keys