Vulnerability Note VU#329230

Multiple Symantec security appliances fail to properly filter port 53/udp traffic

Original Release date: 20 Oct 2004 | Last revised: 20 Oct 2004


A vulnerability exists in multiple Symantec security appliances that could allow a remote attacker to bypass the firewall using a source port of 53/udp.


Symantec's Firewall/VPN appliances and Gateway Security models include a number of services such as tftpd, snmpd, and isakmp. Access to these services from the WAN interface can be restricted through the use of the packet filtering feature of the device. The packet filtering feature contains a vulnerability that could allow a remote attacker to successfully connect to one of these services by specifying a source port of 53/udp.

Affected Products:

    • Symantec Firewall/VPN Appliance 100 (firmware builds prior to build 1.63)
    • Symantec Firewall/VPN Appliance 200/200R (firmware builds prior to build 1.63)
    • Symantec Gateway Security 320 (firmware builds prior to build 622)
    • Symantec Gateway Security 360/360R (firmware builds prior to build 622)


A remote, unauthenticated attacker may be able to establish connections to services in violation of security policies. As a result, an attacker could send packets to these services that are configured to be unreachable from the WAN interface. An attacker could also leverage this flaw to exploit a vulnerability in one of these services. For instance, there is a vulnerability in the Firewall/VPN and Gateway Security appliances that allows a remote attacker to read and modify any SNMP object present on an affected device (VU#173910).


Upgrade Firmware According to the Symantec Advisory, product specific firmware and hotfixes are available via the Symantec Enterprise Support site.

Systems Affected (Learn More)

VendorStatusDate NotifiedDate Updated
Symantec CorporationAffected-20 Oct 2004
If you are a vendor and your product is affected, let us know.

CVSS Metrics (Learn More)

Group Score Vector
Base N/A N/A
Temporal N/A N/A
Environmental N/A N/A



This vulnerability was reported by Symantec. Symantec credits Mike Sues and the Rigel Kent Security & Advisory Services for discovering the vulnerability.

This document was written by Damon Morda.

Other Information

  • CVE IDs: Unknown
  • Date Public: 22 Sep 2004
  • Date First Published: 20 Oct 2004
  • Date Last Updated: 20 Oct 2004
  • Severity Metric: 6.06
  • Document Revision: 14


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