With the Credential Binding enabled (checked), run a job several times while monitoring file handles on the master `lsof -p {pid}`. Notice handles to .../log for the build numbers. Disable (uncheck) Credential Bindings, run several times, notice no handles left open.

I forked the credentials binding plugin and removed `decorateLogger` logic, built, installed on a master. Issue no longer appears. decorateLogger has been obsoleted.

Running Jenkins 2.72 and latest credentials binding plugin.

No credentials have to be defined to see this issue, just enabled (checked).