DNS open Resolver issure

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Joined: Mon Dec 16, 2013 8:02 am
Location: Lebanon, Illinois

DNS open Resolver issure

Postby droth49 » Wed Feb 18, 2015 8:26 am

Help I just recieved this from my service provider. I I don't know how to fix kit?

Charter Communications has been notified that the home networking device connected to your modem participated in a large-scale network impacting distributed denial-of-service (DDoS) attack. The device is acting as a “DNS Open Resolver” and requires configuration changes.

Issue Description – An Open Resolver can allow an entry point for hackers to send out a large flood of network traffic, sometimes called “DDoS or amplification attacks” that cause network congestion and/or disruption to the services in your area. Hackers often share with others the IPs of devices that are known to have open resolver settings thus allowing the device to be used for multiple attacks.

For more information on DNS Open Resolvers, please reference:
US-CERT: US-CERT: http://www.us-cert.gov/ncas/alerts/TA13-088A

We are asking that you take immediate action to remediate this issue.


1) Go to www.whatismyip.com and verify that the IP address assigned to your modem matches the IP address in the subject line of this notification.

2) Go to http://openresolver.com/ and check the IP to see if an “open-resolver” is detected.

3) Once confirmed, we are requesting that you disable the DNS Proxy setting on your router.
Note – If the IP address assigned to your modem has changed, please use the current IP address when checking for the open resolver vulnerability.

4) Once you believe that you have resolved this issue, please verify via http://openresolver.com/ and then reply to this email providing confirmation that you have completed the recommended remediation steps.

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Re: DNS open Resolver issure

Postby bigfoot65 » Wed Feb 18, 2015 9:00 am

Don't believe this is related to Amahi, so we cannot be much assistance.

You need to contact Charter and determine what needs to be done. It could also be a fishing email. I have Charter as an ISP and have not received anything.
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