The proxy DNS service in Symantec Gateway Security (SGS) allows remote attackers to make arbitrary DNS queries to third-party DNS servers, while hiding the source IP address of the attacker. NOTE: another researcher has stated that the default configuration does not proxy DNS queries received on the external interface

The DNS proxy (DNSd) for multiple Symantec Gateway Security products allows remote attackers to poison the DNS cache via a malicious DNS server query response that contains authoritative or additional records.

Symantec Raptor Firewall 6.5 and 6.5.3, Enterprise Firewall 6.5.2 and 7.0, VelociRaptor Models 500/700/1000 and 1100/1200/1300, and Gateway Security 5110/5200/5300 generate easily predictable initial sequence numbers (ISN), which allows remote attackers to spoof connections.

The web proxy component in Symantec Enterprise Firewall (SEF) 6.5.2 through 7.0, Raptor Firewall 6.5 and 6.5.3, VelociRaptor, and Symantec Gateway Security allow remote attackers to cause a denial of service (connection resource exhaustion) via multiple connection requests to domains whose DNS server is unresponsive or does not exist, which generates a long timeout.