Jenkins Maven Plugin 2.17 and earlier bundled a version of the commons-httpclient library with the vulnerability CVE-2012-6153 that incorrectly verified SSL certificates, making it susceptible to man-in-the-middle attacks. Maven Plugin 3.0 no longer has a dependency on commons-httpclient.

Jenkins 2.73.1 and earlier, 2.83 and earlier bundled a version of the commons-httpclient library with the vulnerability CVE-2012-6153 that incorrectly verified SSL certificates, making it susceptible to man-in-the-middle attacks. This library is widely used as a transitive dependency in Jenkins plugins. The fix for CVE-2012-6153 was backported to the version of commons-httpclient that is bundled in core and made available to plugins.

Jenkins Swarm Plugin Client 3.4 and earlier bundled a version of the commons-httpclient library with the vulnerability CVE-2012-6153 that incorrectly verified SSL certificates, making it susceptible to man-in-the-middle attacks.

http/conn/ssl/AbstractVerifier.java in Apache Commons HttpClient before 4.2.3 does not properly verify that the server hostname matches a domain name in the subject's Common Name (CN) or subjectAltName field of the X.509 certificate, which allows man-in-the-middle attackers to spoof SSL servers via a certificate with a subject that specifies a common name in a field that is not the CN field. NOTE: this issue exists because of an incomplete fix for CVE-2012-5783.