plugin/npapi/plugin.cpp in Gnash before 0.8.10 uses weak permissions (world readable) for cookie files with predictable names in /tmp, which allows local users to obtain sensitive information.
https://bugzilla.redhat.com/show_bug.cgi?id=755518
http://www.securityfocus.com/bid/50747
http://www.openwall.com/lists/oss-security/2011/11/21/7
http://www.openwall.com/lists/oss-security/2011/11/21/12
http://www.debian.org/security/2012/dsa-2435
http://secunia.com/advisories/48466
http://secunia.com/advisories/48325
http://lists.opensuse.org/opensuse-updates/2012-03/msg00026.html
http://lists.opensuse.org/opensuse-updates/2012-03/msg00003.html