Norton Internet Security 2001 opens log files with FILE_SHARE_READ and FILE_SHARE_WRITE permissions, which could allow remote attackers to modify the log file contents while Norton Internet Security is running.

Buffer overflow in HTTP Proxy for Symantec Norton Personal Internet Firewall 3.0.4.91 and Norton Internet Security 2001 allows remote attackers to cause a denial of service and possibly execute arbitrary code via a large outgoing HTTP request.