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Old 12-30-2018, 02:49 PM   #1
hack3rcon
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Post Open a port but no service.


Hello.
Can open a port but no service run on it cause a security problem? Nmap can detect that port is open but no service run on it.

Thank you.
 
Old 12-30-2018, 03:14 PM   #2
lazydog
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Are you sure there are no service running? You can check it with the following code:

Code:
netstat -plnt | grep <port#>
 
Old 12-30-2018, 03:28 PM   #3
TB0ne
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Quote:
Originally Posted by hack3rcon View Post
Hello.
Can open a port but no service run on it cause a security problem? Nmap can detect that port is open but no service run on it.

Thank you.
Sorry, no...ports don't 'open' unless a service is running to actually OPEN IT. Does this tie in with your (going on five) other threads now about some generic security issue???
 
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Old 12-30-2018, 06:18 PM   #4
berndbausch
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Quote:
Originally Posted by TB0ne View Post
Sorry, no...ports don't 'open' unless a service is running to actually OPEN IT.
Well the OP probably means “open in the firewall”.

Should not be a problem, until somebody runs a listener by mistake or malice. Normally there is no reason to leave unused ports open in the firewall, so the question is somewhat moot, I think.

Last edited by berndbausch; 12-30-2018 at 06:19 PM.
 
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Old 12-30-2018, 06:55 PM   #5
scasey
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Quote:
Originally Posted by berndbausch View Post
Well the OP probably means “open in the firewall”.

Should not be a problem, until somebody runs a listener by mistake or malice. Normally there is no reason to leave unused ports open in the firewall, so the question is somewhat moot, I think.
While I don't disagree with your analysis, I'd suggest there's not much hope of guessing what this OP "probably" means about anything.

Note that if one isn't running a firewall at all, all ports are "open," but as you say, there's no harm if nothing is listening on the open port.
 
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