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TCP Port 0 Now Blocked

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Community Manager
Community Manager

TCP Port 0 Now Blocked

On 10/20/14 at approximately 2 PM EST, we implemented a block of TCP Port 0 traffic due to continued observation of unusual and likely malicious traffic. If you have an application that began misbehaving around that time, please post here so we can investigate. TCP/0 is a reserved port by IANA, and on testing we performed, we do not believe that any legitimate applications would be impacted. We believe several other ISPs in North America have also recently implemented similar blocks for the same reasons.

 

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Accepted Solution

Re: TCP Port 0 Now Blocked

We are unable to access www.softplan.com

 

also our soft plan software, used for our construction business, is not able to update.   The program has to update (connect to the internet) every time you use it.  If it does not connect within 30 days it will stop working.  We have 6 days left.

 

the rest of the internet comes up just fine.

I checked with soft plan and they do not have our ip addy blocked.

 

this started right around the time this was blocked it.

 

please help, we are dead in the water 

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Accepted Solution

Re: TCP Port 0 Now Blocked

we have a sub contractor with business class with a seperate connection.  He can access the site just fine.  Same if you access it through 3G.  

 

The soft plan people are at a loss.  They checked thier firewall and said they do not have any IPs blocked.

 

I tried with comcast tech support and their modem diags came back fine.  I asked if we could change our IP, they said no.

 

I am at a total loss.

 

Nothing is blocked on the router.  I held down the reset button to hard reset it.  still nothing.

 

It's not just one computer.  There are 6 computers on the network and none of them can access www.softplan.com.  3 computer connect directly into the comcast router.

 

 

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5 REPLIES
kconstco
New Member

Re: TCP Port 0 Now Blocked

We are unable to access www.softplan.com

 

also our soft plan software, used for our construction business, is not able to update.   The program has to update (connect to the internet) every time you use it.  If it does not connect within 30 days it will stop working.  We have 6 days left.

 

the rest of the internet comes up just fine.

I checked with soft plan and they do not have our ip addy blocked.

 

this started right around the time this was blocked it.

 

please help, we are dead in the water 

Trusted Forum Contributor

Re: TCP Port 0 Now Blocked

Odd; the website http://www.softplan.com is loading fine for me ("premium home design software")

 

Can you check with Soft Plan again, and see if their software is using TCP port 0 at all? Because that is the only thing that should be affected by this.

kconstco
New Member

Re: TCP Port 0 Now Blocked

we have a sub contractor with business class with a seperate connection.  He can access the site just fine.  Same if you access it through 3G.  

 

The soft plan people are at a loss.  They checked thier firewall and said they do not have any IPs blocked.

 

I tried with comcast tech support and their modem diags came back fine.  I asked if we could change our IP, they said no.

 

I am at a total loss.

 

Nothing is blocked on the router.  I held down the reset button to hard reset it.  still nothing.

 

It's not just one computer.  There are 6 computers on the network and none of them can access www.softplan.com.  3 computer connect directly into the comcast router.

 

 

nickcopeland12
New Member

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nickcopeland12
New Member

Re: TCP Port 0 Now Blocked

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