It was discovered that pyOpenSSL incorrectly handled memory when handling X509 objects. A remote attacker could use this issue to cause pyOpenSSL to crash, resulting in a denial of service, or possibly execute arbitrary code. This attack appears to be exploitable via Depends on the calling application and if it retains a reference to the memory. This vulnerability appears to have been fixed in 17.5.0.
lists.opensuse.org/opensuse-security-announce/2019-04/msg00014.html
access.redhat.com/errata/RHSA-2019:0085
github.com/advisories/GHSA-p28m-34f6-967q
github.com/pyca/pyopenssl/commit/e73818600065821d588af475b024f4eb518c3509
github.com/pyca/pyopenssl/pull/723
nvd.nist.gov/vuln/detail/CVE-2018-1000807
usn.ubuntu.com/3813-1/