The mixing functions in the random number generator in Libgcrypt before 1.5.6, 1.6.x before 1.6.6, and 1.7.x before 1.7.3 and GnuPG before 1.4.21 make it easier for attackers to obtain the values of 160 bits by leveraging knowledge of the previous 4640 bits. http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2016-6313
