main/java/com/ning/http/client/AsyncHttpClientConfig.java in Async Http Client (aka AHC or async-http-client) before 1.9.0 does not require a hostname match during verification of X.509 certificates, which allows man-in-the-middle attackers to spoof HTTPS servers via an arbitrary valid certificate.
https://wiki.jenkins-ci.org/display/SECURITY/Jenkins+Security+Advisory+2016-06-20
https://github.com/AsyncHttpClient/async-http-client/issues/197
http://www.securityfocus.com/bid/69317
http://rhn.redhat.com/errata/RHSA-2015-1551.html
http://rhn.redhat.com/errata/RHSA-2015-1176.html
http://rhn.redhat.com/errata/RHSA-2015-0851.html