Timo Warns (Warns) 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.
Created libreoffice tracking bugs for this issue Affects: fedora-all [bug 887420]
Created openoffice.org tracking bugs for this issue Affects: fedora-all [bug 887419]
We have various existing security options under tools->options->security->options and tools->options-security->macro security. It's plausible to e.g. extend these options with additional ones like "warn if saving files/creating pdfs if contents of externally linked data will be saved/printed to destination". It's also plausible to attempt to map/follow the macro security concept of trusted sources and low to very high levels to some additional "only allow data to be automatically fetched from links" at low levels of security. Though IMO the default would probably have to be to allow links to at the very least the local filesystem by default for linked graphics, linked videos, master documents etc. But its not particularly easy or quick to implement these. Especially if we want to be able to control access to local resources.