DOS Attack?

From: Shawn Wall (sjwall_at_shaw.ca)
Date: 11/25/04

  • Next message: Andrew Shore: "RE: cisco IOS firewall terminating pptp" 
    Date: Wed, 24 Nov 2004 19:22:40 -0700
To: security-basics@securityfocus.com

    Hi List,

    I'm currently experiencing network outages due to what appears to be DOS
    attacks. I'm running a wireless ISP using a Cisco 2611 and CBAC and I have a
    /24 public address range. During the outage I can see traffic from a single
    external host sending thousands of packets to a single internal host. I
    don't have port 80 inbound open in my ACLs so I don't understand how the
    external host is even able to contact the internal host to begin with.
    Secondly, how is it possible for an attack on 1 internal host to cripple the
    rest of my network? Any feedback would be welcome. Thanks.

    shawn
     

  • Next message: Andrew Shore: "RE: cisco IOS firewall terminating pptp"

    Relevant Pages

    • Re: DOS Attack?
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    • Re: DOS Attack?
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