Mozilla community member Vincent Lefevre reported that on Linux systems, web content can access data saved to the clipboard when a user attempts to paste a selection with a middle-click instead of pasting the selection content. This allows for possibly private data in the clipboard to be inadvertently disclosed to web content. Windows and OS X systems are not affected by this issue. In general these flaws cannot be exploited through email in the Thunderbird and Seamonkey products because scripting is disabled, but are potentially a risk in browser or browser-like contexts. External Reference: http://www.mozilla.org/security/announce/2013/mfsa2013-112.html Acknowledgements: Red Hat would like to thank the Mozilla project for reporting this issue. Upstream acknowledges Vincent Lefevre as the original reporter. Statement: This issue does not affect the version of firefox and thunderbird as shipped with Red Hat Enterprise Linux 5 and 6