Cisco IOS 12.1 Large TCP Scan Denial of Service Vulnerability

BID:4947

Info

Cisco IOS 12.1 Large TCP Scan Denial of Service Vulnerability

Bugtraq ID: 4947
Class: Failure to Handle Exceptional Conditions
CVE:
Remote: Yes
Local: No
Published: Jun 05 2002 12:00AM
Updated: Jun 05 2002 12:00AM
Credit: Reported by Andrew Vladimirov <[email protected]>.
Vulnerable: Cisco IOS 12.1
Not Vulnerable:

Discussion

Cisco IOS 12.1 Large TCP Scan Denial of Service Vulnerability

IOS is the Internet Operating System, used on Cisco routers. It is distributed and maintained by Cisco.

Some versions of IOS may suffer from a denial of service condition when large port scans are performed through the vulnerable router. Reportedly, scanning a single host on all 65535 possible ports or scanning a class C network block for a single port are sufficient to exploit this vulnerability.

This vulnerability has been reported to exist on a Cisco 2611 router running IOS 12.1(6.5). Cisco has reported that they are unable to reproduce this problem. It is possible that this issue is the result of a configuration error or site specific conditions.

Exploit / POC

Cisco IOS 12.1 Large TCP Scan Denial of Service Vulnerability

Andrew Vladimirov <[email protected]> reports that this may be accomplished with the tool nmap.

Solution / Fix

Cisco IOS 12.1 Large TCP Scan Denial of Service Vulnerability

Solution:
Currently we are not aware of any vendor-supplied patches for this issue. If you feel we are in error or are aware of more recent information, please mail us at: [email protected] <mailto:[email protected]>.

References

Cisco IOS 12.1 Large TCP Scan Denial of Service Vulnerability

References:

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