LibreOffice opens a TCP port on localhost and doesn't start if the port is blocked

[xor]

I am on Kubuntu 14.04 amd64 with latest packages of everything (libreoffice-core = Version: 1:4.2.4-0ubuntu2).

LibreOffice was working fine until about 2014-06-22 - thats the modification date of the last file which I edited with it.
Somewhere between 2014-06-22 and 2014-06-24, a package was auto-updated and now it won't start anymore.
It hangs at the splash screen.

I've figured out the reason: LibreOffice opens a random TCP port on 127.0.0.1 and tries to connect to it. Because I have blocked connections to localhost in my firewall, the connection fails, resulting in the hang. If I open the port, it works.
I cannot add a firewall rule to fix this permanently though because the port is chosen randomly.
And why does a text editor need a TCP port anyway?

Please do one of the following:
- Check whether this is debug functionality which has accidentally been left in. It might be a security issue, so I filed this as security. Please remove the flag if it is not.
- Add a way of configuring it to disable the TCP stuff.
- Add a way of configuring which port is used .

Please do not tell me that denying access to localhost is nonsense: There are certain daemons which do not provide authentication mechanisms, and there are multiuser machines. If I want to protect those daemons on a multiuser machine I need to deny localhost connections by default and work with whitelisting allowed types of connections.

[Seth Arnold (seth-arnold)]

Thanks for this report; I'm unmarking the 'security' flag after a quick inspection of the changes introduced in the most recent update show significant reworking of bluetooth connectivity including some work for remotecontrol devices. It seems more likely to me that requiring a TCP port to localhost is from these than a mistaken debug mode.

Thanks

[Marcus Tomlinson (marcustomlinson)]

This release of Ubuntu is no longer receiving maintenance updates. If this is still an issue on a maintained version of Ubuntu please let us know.

[Launchpad Janitor (janitor)]

[Expired for libreoffice (Ubuntu) because there has been no activity for 60 days.]