The bgp_capability_orf function in bgpd in Quagga 0.99.20.1 and earlier allows remote attackers to cause a denial of service (assertion failure and daemon exit) by leveraging a BGP peering relationship and sending a malformed Outbound Route Filtering (ORF) capability TLV in an OPEN message.

Buffer overflow in the OSPFv2 implementation in ospfd in Quagga before 0.99.20.1 allows remote attackers to cause a denial of service (daemon crash) via a Link State Update (aka LS Update) packet containing a network-LSA link-state advertisement for which the data-structure length is smaller than the value in the Length header field.

The BGP implementation in bgpd in Quagga before 0.99.20.1 does not properly use message buffers for OPEN messages, which allows remote attackers to cause a denial of service (assertion failure and daemon exit) via a message associated with a malformed Four-octet AS Number Capability (aka AS4 capability).

Buffer overflow in the ospf_ls_upd_list_lsa function in ospf_packet.c in the OSPFv2 implementation in ospfd in Quagga before 0.99.20.1 allows remote attackers to cause a denial of service (assertion failure and daemon exit) via a Link State Update (aka LS Update) packet that is smaller than the length specified in its header.