Version 1.51 affected by multiple security vulnerabilitites

[Marc Peña]

The version of BouncyCastle available on Xenial is affected by multiple security vulnerabilities:

https://people.canonical.com/~ubuntu-security/cve/CVE-2015-6644
https://people.canonical.com/~ubuntu-security/cve/CVE-2016-1000338
https://people.canonical.com/~ubuntu-security/cve/CVE-2016-1000339
https://people.canonical.com/~ubuntu-security/cve/CVE-2016-1000340
https://people.canonical.com/~ubuntu-security/cve/CVE-2016-1000341
https://people.canonical.com/~ubuntu-security/cve/CVE-2016-1000342
https://people.canonical.com/~ubuntu-security/cve/CVE-2016-1000343
https://people.canonical.com/~ubuntu-security/cve/CVE-2016-1000344
https://people.canonical.com/~ubuntu-security/cve/CVE-2016-1000345
https://people.canonical.com/~ubuntu-security/cve/CVE-2016-1000346
https://people.canonical.com/~ubuntu-security/cve/CVE-2016-1000352

I guess that the options are:
- Apply the two missing patches in Bionic version:
https://people.canonical.com/~ubuntu-security/cve/CVE-2018-1000180
https://people.canonical.com/~ubuntu-security/cve/CVE-2018-1000613
And backport it to Xenial.

- Using the version with the security patches from Debian Stretch (1.56): https://metadata.ftp-master.debian.org/changelogs//main/b/bouncycastle/bouncycastle_1.56-1+deb9u2_changelog