Vulnerability Note VU#125156

Ethereal contains multiple vulnerabilities in the UCP protocol dissector

Original Release date: 25 Mar 2004 | Last revised: 25 Mar 2004


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

Systems Affected (Learn More)

VendorStatusDate NotifiedDate Updated
EtherealAffected-25 Mar 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



Ethereal credits Stefan Esser for reporting this vulnerability.

This document was written by Damon Morda.

Other Information

  • CVE IDs: CAN-2004-0176
  • Date Public: 22 Mar 2004
  • Date First Published: 25 Mar 2004
  • Date Last Updated: 25 Mar 2004
  • Severity Metric: 9.82
  • Document Revision: 9


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