In the Bouncy Castle JCE Provider version 1.55 and earlier the DSA key pair generator generates a weak private key if used with default values. If the JCA key pair generator is not explicitly initialised with DSA parameters, 1.55 and earlier generates a private value assuming a 1024 bit key size. In earlier releases this can be dealt with by explicitly passing parameters to the key pair generator.
access.redhat.com/errata/RHSA-2018:2669
access.redhat.com/errata/RHSA-2018:2927
github.com/advisories/GHSA-rrvx-pwf8-p59p
github.com/bcgit/bc-java
github.com/bcgit/bc-java/commit/50a53068c094d6cff37659da33c9b4505becd389#diff-5578e61500abb2b87b300d3114bdfd7d
lists.apache.org/thread.html/708d94141126eac03011144a971a6411fcac16d9c248d1d535a39451@%3Csolr-user.lucene.apache.org%3E
lists.debian.org/debian-lts-announce/2018/07/msg00009.html
nvd.nist.gov/vuln/detail/CVE-2016-1000343
security.netapp.com/advisory/ntap-20181127-0004
usn.ubuntu.com/3727-1
www.oracle.com/security-alerts/cpuoct2020.html