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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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Issue with Netgear GS108T Managed Switch and Jumbo Frames

I recently purchased a Netgear GS108T managed switch and I am trying to configure jumbo packets between my NAS (Thecus N4100Pro), PC and managed switch. I should mention the fact that I was able to use jumbo frames between my PC and NAS before I…
Richie086
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using nmap to guess remote OS and probe service details on a single port only

I am looking at scanning with nmap a large network in order to identify the OS of devices (-O--osscan-limit) probe for details of a service on a single port (I would have used -sV for all open ports) The problem is that -sV will probe all the…
WoJ
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646/tcp open unknown

when I make nmap localhost I get PORT STATE SERVICE 22/tcp open ssh 25/tcp open smtp 111/tcp open rpcbind 631/tcp open ipp 646/tcp open unknown what is the port 646 ?
JuanPablo
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IPtables: is there a minimum UDP packet size for a DNS lookup?

IPtables for a virtual dedicated server. I would like to block UDP scans and I was wondering whether there's a minimum packet size for a DNS lookup? Nmap sends 0-byte UDP packets (source : http://nmap.org/bennieston-tutorial/ ), but there're…
Kris
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Port is open on machine A but it is not visible from machine B in Nmap

I have a virtualized CentOS machine with a software that is listening on port 8080. I have turned off SELinux and flushed all iptables (so now there are no rules set). I have checked with netstat -nap | grep 8080 that the port is really open and it…
Rox
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How to find out that SMTP server is in open relay?

I used nmap for network security testing. It found that SMTP server was in open relay. Here is the output: nmap --script smtp-open-relay testwww.confidesk.com PORT STATE SERVICE 25/tcp open smtp |_smtp-open-relay: Server is an open relay…
Andrei Botalov
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NMap - running as root yields different response than running as another user

nmap -eeth1 [hostname] -p80 Running that command as root uses interface one and fails as expected (interface one is on a subnet blocked by the host.) Using interface 0 succeeds as it should. However, if I switch to user zabbix then the above…
Joshua Enfield
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Why can NMAP not show some ports?

when I do "nmap localhost", some open ports are listed and others aren't. For Example SSH on 22 is listed, but SSH on 10022 is not. Host's port 10022 in my case is NAT port forwarding to a VBoxHeadless VM SSH, and Host's port 22 is it's own SSH…
Ivan
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nmap vulnerability scan reports " smtps on port 465 ssl-dh-params" vulnerability, on Ubuntu 20.04 webserver. How to close the vulnerabilty?

I am running an Ubuntu 20.04 LEMP (Linux, Nginx, MariaDb, PHP) email/web server. I am also doing some nmap vulnerability tests form my MacOS Client machine. On MacOS, I am using Oh My Zsh! with the nmap plugin enabled. To do some vulnerability tests…
DanRan
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Nmap unable to resolve hostnames

I have tried running several nmap commands and I can't get the results to return host names. My results look like this: Nmap scan report for 10.2.16.253 Host is up (0.0025s latency). All 1000 scanned ports on 10.2.16.253 are in ignored states. Not…
UbuntuNoob
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Is there a built-in way to proxy SSH through socks5?

I have a Socks5 proxy that uses username/password authentication. I can use it with SSH using NCAT in the ProxyCommand: ssh -o ProxyCommand="ncat --proxy-type socks5 --proxy-auth username:password --proxy socks5.proxy.domain:1080 %h %p"…
ykaganovich
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Unable to ping scan my machine (but I can ping)

I need to perform an nmap scan on all of the (responding) IPs in an array of VLANs. The command is nested in a PowerShell for loop and looks something like this: nmap.exe -Pn -T4 -A -oG [FILE].txt -oX [FILE].xml "$($subnet).0/24" We had to add the…
TheCube
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Nmap reporting open http-proxy on 8080, but none is running

While executing the following command from my Mac OSX: nmap -PN server.com It reports the following: Starting Nmap 7.70 ( https://nmap.org ) at 2019-04-18 16:14 EDT Nmap scan report for server.com (9.9.9.9) Host is up (0.020s latency). Not…
Khom Nazid
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NPing gives significantly less time on `TCP Connect` than `TCP`

I'm using NPing (NMap's pinging tool) to measure latency on specific servers that may not respond to ICMP. Also, servers do not usually run HTTP(S) and I only check latency on a specific TCP port related to the game counter-strike. I always try…
ruasoliveira
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Why does nmap show port 25 as open? Server's firewall should block port 25

nmap 7.70 executed remotely shows the server's port 25 as open. However, the firewall on my VPS server only opens ssh, http and https services. On the laptop: nmap x.x.x.x Not shown: 996 filtered ports PORT STATE SERVICE 22/tcp open …
user2923322
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