The unpacker::redirect_stdio function in unpack.cpp in unpack200 in OpenJDK 6, 7, and 8, and Oracle Java JDK, does not securely create temporary files when a log file cannot be opened, which allows local users to overwrite arbitrary files via a symlink attack on /tmp/unpack.log. http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2014-1876
