This affects all versions of package org.nanohttpd:nanohttpd. Whenever an HTTP Session is parsing the body of an HTTP request, the body of the request is written to a RandomAccessFile when the it is larger than 1024 bytes. This file is created with insecure permissions that allow its contents to be viewed by all users on the host machine. **Workaround:** Manually specifying the -Djava.io.tmpdir= argument when launching Java to set the temporary directory to a directory exclusively controlled by the current user can fix this issue.