search menu icon-carat-right cmu-wordmark

CERT Coordination Center

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

Vulnerability Note VU#329230

Original Release Date: 2004-10-20 | Last Revised: 2004-10-20


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

Vendor Information


Symantec Corporation Affected

Updated:  October 20, 2004



Vendor Statement

We have not received a statement from the vendor.

Vendor Information

The vendor has not provided us with any further information regarding this vulnerability.


Please refer to Symantec Advisory SYM04-013.

If you have feedback, comments, or additional information about this vulnerability, please send us email.

CVSS Metrics

Group Score Vector



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: None
Severity Metric: 6.06
Date Public: 2004-09-22
Date First Published: 2004-10-20
Date Last Updated: 2004-10-20 14:36 UTC
Document Revision: 14

Sponsored by CISA.