bvlc.c in skarg BACnet Protocol Stack bacserv 0.9.1 and 0.8.5 is affected by a Buffer Overflow because of a lack of packet-size validation. The affected component is bacserv BACnet/IP BVLC forwarded NPDU. The function bvlc_bdt_forward_npdu() calls bvlc_encode_forwarded_npdu() which copies the content from the request into a local in the bvlc_bdt_forward_npdu() stack frame and clobbers the canary. The attack vector is: A BACnet/IP device with BBMD enabled based on this library connected to IP network. The fixed version is: 0.8.6.