When updating a plugin in Hudson 1.341 I get a NPE:

java.lang.NullPointerException
at hudson.security.ContainerAuthentication.getPrincipal(ContainerAuthentication.java:79)
at hudson.security.ContainerAuthentication.getName(ContainerAuthentication.java:91)
at hudson.model.UpdateCenter$DownloadJob.run(UpdateCenter.java:691)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:417)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:269)
at java.util.concurrent.FutureTask.run(FutureTask.java:123)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:651)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:676)
at java.lang.Thread.run(Thread.java:595)

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