CVE-2017-8798: Integer signedness error in MiniUPnP MiniUPnPc v1.4.20101221
through v2.0 allows remote attackers to cause a denial of service or
possibly have unspecified other impact.
For more details including a PoC, see:
https://github.com/tintinweb/pub/tree/master/pocs/cve-2017-8798
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>