Gentoo Linux Security Advisory GLSA 200603-15 – Lincoln Stein discovered that Crypt::CBC fails to handle 16 bytes long initializiation vectors correctly when running in the RandomIV mode, resulting in a weaker encryption because the second part of every block will always be encrypted with zeros if the blocksize of the cipher is greater than 8 bytes. Versions less than 2.17 are affected.
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/44792/glsa-200603-15.txt
Source: https://packetstormsecurity.com/files/44792/Gentoo-Linux-Security-Advisory-200603-15.html