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CERT Coordination Center


Cisco IOS vulnerable to deferred DoS via SYN scan to certain TCP port ranges

Vulnerability Note VU#178024

Original Release Date: 2001-10-25 | Last Revised: 2001-10-25

Overview

Cisco Internetwork Operating System (IOS) may reload unexpectedly after being scanned on certain ports.

Description

Certain versions of Cisco IOS contain a vulnerability that allows the router to enter an unstable state after receiving a connection attempt on any TCP port in the following ranges: 3100-3999, 5100-5999, 7100-7999, and 10100-10999. In this state, the router will reload at the next execution of "show running-config," "write memory," or any command that causes the configuration file to be accessed.

Impact

Attackers may cause Cisco routers to reload and cause a denial of service.

Solution

Review Cisco Systems's security advisory to determine which versions of IOS are vulnerable and which version you should obtain to eliminate this vulnerability. The advisory is available at:

http://www.cisco.com/warp/public/707/ios-tcp-scanner-reload-pub.shtml

None.

Vendor Information

178024
Expand all

Cisco

Updated:  October 25, 2001

Status

  Vulnerable

Vendor Statement

See the information in http://www.cisco.com/warp/public/707/ios-tcp-scanner-reload-pub.shtml

Vendor Information

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

Addendum

The CERT/CC has no additional comments at this time.

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


CVSS Metrics

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

References

Credit

Thanks to Cisco Systems for reporting this vulnerability.

This document was written by Shawn Van Ittersum.

Other Information

CVE IDs: CVE-2001-0750
Severity Metric: 11.81
Date Public: 2001-05-24
Date First Published: 2001-10-25
Date Last Updated: 2001-10-25 23:44 UTC
Document Revision: 11

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