From $URL : Timo Warns (Warns@Pre-Sense.DE) reported publicly that OpenOffice and LibreOffice (as well as other Office Suites) fail to appropriately warn users when a file with embedded content is opened. Additionally it is not possible to disable the opening of embedded content within files. This can be used to add tracking behavior to files or to deliver additional files that can potentially exploit other security issues when parsed to the user. Additionally if the file is converted (e.g. to a PDF) and then saved the converted file may contain a direct copy of the embedded data, thus if something sensitive if referenced (such as ~/.ssh/id_rsa) this information may then be exposed if the resulting file is shared.
LibreOffice states this is fixed in 4.2 by introducing a stealth mode: http://whatofhow.wordpress.com/2013/12/02/stealth-mode/ (from https://bugs.freedesktop.org/show_bug.cgi?id=58295#c2 ). If that can be verified it is already stabilized.
(In reply to Kristian Fiskerstrand from comment #1) > LibreOffice states this is fixed in 4.2 by introducing a stealth mode: > http://whatofhow.wordpress.com/2013/12/02/stealth-mode/ (from > https://bugs.freedesktop.org/show_bug.cgi?id=58295#c2 ). If that can be > verified it is already stabilized. The option is there in app-office/libreoffice-bin-5.0.3.2. Upstream has closed this as invalid due to lack of information. Warn the user via ewarn or release a GLSA, thoughts?
*** Bug 447378 has been marked as a duplicate of this bug. ***
Per my previous comments and that of dilfridge from bug 447378 upstream has designed functionality to provide a "stealth mode" in the newest tree stable versions of libreoffice. Upstream has closed this as WONTFIX. No reply from maintainers regarding a warning for users.