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Ethereal contains multiple vulnerabilities in the UCP protocol dissector

Vulnerability Note VU#125156

Original Release Date: 2004-03-25 | Last Revised: 2004-03-25


Ethereal contains multiple buffer overflows in the Universal Control Protocol (UCP) protocol dissector. These vulnerabilities could allow a remote, unauthenticated attacker to execute arbitrary code.


Ethereal is a network traffic analysis package. It includes the ability to decode packets containing UCP data. There are three buffer overflow vulnerabilities in the way the UCP protocol dissector decodes packets containing UCP data. These vulnerabilities could be exploited by a remote, unauthenticated attacker by sending a specially crafted UCP packet containing an overly long string, integer, or time field value. Exploitation of these vulnerabilities could result in arbitrary code execution.

According to the e-matters Security Advisory:

To exploit this vulnerability over the wire an attacker must be able to fit more than BUFSIZ bytes into one TCP packet. This means it is only exploitable on the wire if the system has a MTU bigger than BUFSIZ. BUFSIZ is 8192 on glibc systems, 1024 on BSD systems and 512 on Windows systems.


A remote, unauthenticated attacker could execute arbitrary code on the vulnerable system.



Upgrade to version 0.10.3 or later.

Note: Ethereal is considered BETA software at this time.

Disable Dissector

If you are unable to upgrade to version 0.10.3 or later, you can disable the UCP protocol dissector by performing the following actions in Ethereal:

(for Ethereal versions 0.9.x)
1) Select Edit->Protocols
2) Deselect the UCP protocol dissector from the list

(for Ethereal versions 0.10.x)
1) Select Analyze->Enabled Protocols
2) Disable the UCP protocol dissector from the list by unchecking its "Status" checkbox

Vendor Information


Ethereal Affected

Updated:  March 25, 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 the Ethereal Security Bulletin at

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

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Ethereal credits Stefan Esser for reporting this vulnerability.

This document was written by Damon Morda.

Other Information

CVE IDs: CVE-2004-0176
Severity Metric: 9.82
Date Public: 2004-03-22
Date First Published: 2004-03-25
Date Last Updated: 2004-03-25 22:05 UTC
Document Revision: 13

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