IcedTea6 before 1.7.4 does not properly check property access, which allows unsigned apps to read and write arbitrary files.
https://security-tracker.debian.org/tracker/CVE-2010-2548
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2010-2548
http://blog.fuseyism.com/index.php/2010/07/28/icedtea6-174-released/