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Re: CVE Request (minor) -- osc: Improper sanitization of terminal emulator escape sequences when displaying build log and build status
From: Marcus Meissner <meissner () suse de>
Date: Tue, 28 Feb 2012 23:44:07 +0100

On Tue, Feb 28, 2012 at 06:56:52PM +0100, Jan Lieskovsky wrote:
Hello Kurt, Steve, Marcus, vendors,

  a security flaw was found in the way osc, the Python language based 
line client for the openSUSE build service, displayed build logs and build
status for particular build. A rogue repository server could use this flaw 
modify window's title, or possibly execute arbitrary commands or overwrite
files via a specially-crafted build log or build status output containing an
escape sequence for a terminal emulator.

[1] https://bugzilla.novell.com/show_bug.cgi?id=749335
[2] https://bugzilla.redhat.com/show_bug.cgi?id=798353

I need to conclude, I don't know how OBS repositories work (if there is a 
of a rogue server being present). In any case, this issue is on the border
(pretty unlikely someone could alter content of OBS package during build --
in that case there would be more urgent issues than just particular terminal
window title change).

But strictly taken, the trust boundary is crossed in the moment, someone
would schedule OBS build and wouldn't expect the build log / status can
perform terminal "side" effect yet.

Marcus, please correct me if you don't agree this should get a CVE 

If no one having objections and request appropriate, could you allocate one?

I am not fully convinced it needs a CVE.

It basically boils down to the old "logfile with content that might be controlled
by an attacker pasted raw to a terminal" issue.

There is some more control on the person who builds a specific package what is output
thant there usually is in logfiles though.

A rogue server is unlikely, however a malicious packager could echo "bad escape code"
in his build and then ask for help on our IRC channels or mailinglists with package Y on project X.
(anyone can create an account and build packages ... and asking for help is not uncommon)
e.g. with "look at logfile with: 'osc buildlog home:user foopackage standard i586'.)

Ciao, Marcus

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