The \Device\SymEvent driver in Symantec Norton Personal Firewall 2006 9.1.0.33, and other versions of Norton Personal Firewall, Internet Security, AntiVirus, SystemWorks, Symantec Client Security SCS 1.x, 2.x, 3.0, and 3.1, Symantec AntiVirus Corporate Edition SAVCE 8.x, 9.x, 10.0, and 10.1, Symantec pcAnywhere 11.5 only, and Symantec Host, allows local users to cause a denial of service (system crash) via invalid data, as demonstrated by calling DeviceIoControl to send the data.

SYMNDIS.SYS in Symantec Norton Internet Security 2003 and 2004, Norton Personal Firewall 2003 and 2004, Client Firewall 5.01 and 5.1.1, and Client Security 1.0 and 1.1 allow remote attackers to cause a denial of service (infinite loop) via a TCP packet with (1) SACK option or (2) Alternate Checksum Data option followed by a length of zero.

Multiple vulnerabilities in SYMDNS.SYS for Symantec Norton Internet Security and Professional 2002 through 2004, Norton Personal Firewall 2002 through 2004, Norton AntiSpam 2004, Client Firewall 5.01 and 5.1.1, and Client Security 1.0 through 2.0 allow remote attackers to cause a denial of service or execute arbitrary code via (1) a manipulated length byte in the first-level decoding routine for NetBIOS Name Service (NBNS) that modifies an index variable and leads to a stack-based buffer overflow, (2) a heap-based corruption problem in an NBNS response that is missing certain RR fields, and (3) a stack-based buffer overflow in the DNS component via a Resource Record (RR) with a long canonical name (CNAME) field composed of many smaller components.

The SYMDNS.SYS driver in Symantec Norton Internet Security and Professional 2002 through 2004, Norton Personal Firewall 2002 through 2004, Norton AntiSpam 2004, Client Firewall 5.01 and 5.1.1, and Client Security 1.0 through 2.0 allows remote attackers to cause a denial of service (CPU consumption from infinite loop) via a DNS response with a compressed name pointer that points to itself.

The GUI functionality for an interactive session in Symantec LiveUpdate 1.70.x through 1.90.x, as used in Norton Internet Security 2001 through 2004, SystemWorks 2001 through 2004, and AntiVirus and Norton AntiVirus Pro 2001 through 2004, AntiVirus for Handhelds v3.0, allows local users to gain SYSTEM privileges.

Cross-site scripting (XSS) vulnerability in Symantec Norton Internet Security 2003 6.0.4.34 allows remote attackers to inject arbitrary web script or HTML via a URL to a blocked site, which is displayed on the blocked sites error page.