Credentials transmitted in plain text by Jenkins Logstash Plugin

Logstash Plugin stores credentials in its global configuration file jenkins.plugins.logstash.LogstashConfiguration.xml on the Jenkins controller as part of its configuration.

While the credentials are stored encrypted on disk, they are transmitted in plain text as part of the configuration form by Logstash Plugin 2.3.1 and earlier. This can result in exposure of the credential through browser extensions, cross-site scripting vulnerabilities, and similar situations.

Logstash Plugin 2.3.2 transmits the credentials in its global configuration encrypted.