Repro steps:

1. Launch https://jenkins-ci.org/jenkins.jnlp from a Windows machine running JDK 1.8.0_112.
2. Error dialog will pop up: Your security settings have blocked an application from running due to missing a "Permissions" manifest attribute in the main jar.

Reproducible 100% of the time.

See http://docs.oracle.com/javase/7/docs/technotes/guides/jweb/security/manifest.html and http://stackoverflow.com/a/21427782/14731 for an explanation of the Permissions attribute.