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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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iptables rule to drop SYN and FIN attacks

From a Trustwave report, we are trying to set our server to block this type of request but after trying several combinations of rules, we can still see the ports. Could anyone give me a hint or the set of necessary rules to block this request? I'm…
shadow_of__soul
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Can't get nmap to work under Windows 7 64 bit

I'm trying to install and run the nmap tool to test my server, but it keeps saying Note: Host seems down. If it is really up, but blocking our ping probes, try -P0 and showing all the server ports are closed. Which is not true - the server is up…
jitbit
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use of nmap clogged my network

I was using nmap to scan the mac addresses of my network.What I found was internet connections and rest of network services badly clogged the users were not able to connect to internet.After messing with different things some times later we noticed…
Registered User
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How to Hide OS Fingerprint of Virtual Machine?

Is it possible to make a linux virtual machine appear as the host machine to a network tool like nmap or Blue's Port Scanner without recompiling the kernel?
Jeremy Battle
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tcp port 554 open

I was running a routine security check of the machines I manage today and found in my nmap scans that TCP/554 is open, although when I run 'netstat -an' on the machine itself it doesn't show up, same result if I nmap the host locally. I then tried…
Hilton D
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nmap failing to resolve some IPs to hostname

My objective here is to get nmap to resolve IPs to hostnames without the --system-dns flag or the --dns-servers option. When I issue the following nmap command without the --system-dns flag or --dns-servers option, 192.168.0.16 is resolved to…
JeremyCanfield
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Ho to use NMAP to check if a port is filtered by a firewall?

I have the following situation. I should have the access to a VM via SSH but trying to connect to this machine I obtain no response. I suspect that some firewall rules are blocking my request (so it should be considered as filtered). How can I…
AndreaNobili
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why doesn't arp-scan find any devices when nmap does?

When I run nmap -sn 192.168.0.0/24 I get the result: Nmap scan report for 192.168.0.1 Host is up (0.16s latency). Nmap scan report for 192.168.0.103 Host is up (0.19s latency). Nmap scan report for 192.168.0.124 Host is up (0.11s latency). Nmap…
Qualphey
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Why do some unknown hosts show up with nmap option-sL , and not with -sn [and do I need to worry about them]?

Initial Disclosure I am not a network engineer and my expertise in this area is low. Background while using nmap 7.70 with nmap -sL to look for the IP address of a known device on our local network [behind VPN and firewall], I noticed two entries…
Mister October
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Nmap - Specify which probe(s) to use?

I'm trying to determine if it's possible to specify probe types for nmap to use. For example, I want to scan a subnet (say 192.168.0.0/24) and probe every port on every host to see if a web server is running on that port - the goal being to find a…
SuperStudent
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In Linux server - how to check if established TCP port connection supports TLS 1.2

I have a Linux server that has an established TCP port connection to a client. Can I somehow check if the connection on this port supports TLS 1.2 with any of the networking commands on a basic Linux installation or with the command nmap?
user8225639
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ssh-keyscan does not reveal DSA ssh-dss key

I am using ssh-keyscan to obtain public keys for a couple of SSH servers. One of my appliances only supports DSA / ssh-dss. ssh-keyscan with the "-t dsa" option is not able to get the public key while the Nmap script ssh-hostkey in fact is able to…
Johannes Weber
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Port scanning and Windows Firewall

I am trying to understand the results I am getting when scanning ports on a machine that has an active built-in Windows Firewall. My test environment has two Windows 7 machines running in Hyper-V VMs connected directly with an internal virtual…
David
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TLS version scan discrepancy between nmap, openssl, ssllab

I am trying to scan an endpoint to see what TLS version it is running and I am seeing some discrepancy between the nmap scan and the openssl scan. Scanning the same host I see only TLSv1.0 from nmap (7.40) and I can see TLSv1.2 with openssl…
YTKColumba
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Understanding the nmap ssl-enum-ciphers script

I'm testing Tomcat SSL configuration of my server and I was using the ssl-enum-ciphers script of nmap and the following warning appears: Key exchange parameters of lower strength than certificate key What does this mean? I can't find meaningful…
John Giotta
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