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Questions tagged [nmap]

Nmap (Network Mapper) is a security scanner originally written by Gordon Lyon (also known by his pseudonym Fyodor Vaskovich) used to discover hosts and services on a computer network, thus creating a "map" of the network.

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Run ncat in background

from some time I'm trying to resolve very annoying issue: I need to have simple server which will listen on particular TCP port and throw all information which it recieve to trash. I'm doing it by running ncat: ncat -l 192.168.1.1 49111 -k -m…
Paweł Wojtal
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One device shows down when more than 160 ip addresses are scanned with nmap

This is bugging me. I consistently have a single device that fails to respond to an nmap scan when more than ~160 IP addresses are specified. I seem to get mixed results between 150-160 IP addresses and anything less it always responds. The device…
Scottz
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Port suddenly closed. How to re-open?

I've written a software module in PHP that manages the saving of data in different data stores (MySQL, ElasticSearch and Redis). To test the module, I've created several test plans in Apache JMeter, including some that make a lot of concurrent…
jgxvx
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nmap shows services I'm unaware of

When I run nmap on my server it says the following ports are open, but my iptables have no rules explicitly allowing them. 135/tcp filtered msrpc 139/tcp filtered netbios-ssn 445/tcp filtered microsoft-ds It's a debian web server running…
chovy
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Why does scanlogd miss port scans?

I am running scanlogd to detect port scans. I have observed the following to generate a log message in /var/log/syslog. When I use zenmap (nmap gui) to port scan this system from another computer on the same subnet Using nmap to scan the system…
Lord Loh.
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ping and identify Cisco model without physical access or login?

There are several Cisco devices on my network which I can find with ping or nmap but I have no idea what the type (e.g. switches, routers) or specific model is. Is there some way to find this out without physical access or having a login to any of…
T. Webster
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Port 443 is open but IP tables denies it

When I run the following command on my Ubuntu instance: $ nmap host I see that port 443 is open: Starting Nmap 5.21 ( http://nmap.org ) at 2013-03-19 05:36 PDT Nmap scan report for [host redacted] (ip address redacted) Host is up (0.000034s…
Chris
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Windows AdvFirewall and nmap scans

I come from a Unix background but got the task of configuring a Windows firewall on a public facing server. I find awkward that any nmap scan I perform against the public IP reports all TCP ports from 1 to 65389 as open regardless of the Windows…
manthis
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nmap scan only state of port

Is it possible with nmap to check only the state of a port whether- open, closed or filtered and NOT the services behind it? The aim is to speed up scan results. Since UDP scan is also involved it is taking forever to complete. That aside what…
user492160
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Nmap SYN Scan blocks all connections?

I have ServerA (running Ubuntu 12.04 (IP: 10.10.10.200)), a KVM DomU of an also Ubuntu Dom0 that is trying to perform a scan against ServerB-ServerZ (Mixed OS (IPs:10.10.10.20-199)) using the command: nmap -vv --stats-every 5s -sS -R -p 1-65535…
Onitlikesonic
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What's going on with traceroute?

The following is what happens when I run traceroute from a certain location: # traceroute google.com traceroute to google.com (74.125.227.39), 30 hops max, 60 byte packets 1 gateway.local.enactpc.com (10.0.0.1) 0.138 ms 0.101 ms 0.084 ms 2 *…
Soviero
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Can't Ping host, nmap detects it?

I have a simple question that I'm trying to wrap my head around. I know this requires knowledge of my internal network, but at a glance, what do you guys think.. I cannot ping a host in my network (nor can I arping the host), however nmap can detect…
slugman
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finding live hosts with nmap

I'm trying to find live hosts on the network with nmap: nmap -sP 192.168.3.0/24 Starting Nmap 5.21 ( http://nmap.org ) at 2012-04-10 10:28 EEST Nmap scan report for km-localhost (192.168.3.1) Host is up. Nmap scan report for km-localhost…
Alec T
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Nmap / Batch: alert if only ports usually closed are opened?

Context I check open ports on my server with a scheduled batch file: nmap.exe server1 server2 server3 etc >> log.txt Usually 21, 22, 80, 443 and 3389 are opened. Now I want to send an email if only other ports are opened. I saw there is Nmap Script…
GG.
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iptables has port 80 open but nmap shows it closed

I'm having some troubles getting a Debian webserver to open up port 80 for HTTP traffic. In my iptables, I opened up port 80 using the following commands: iptables -A INPUT -p tcp --dport 80 -j ACCEPT iptables -A INPUT -p udp --dport 80 -j…
zeptonaut
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