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Questions tagged [ports]

In computer networking a port is a software construct serving as a communications endpoint in a computer's host OS.

2
votes
1answer
268 views

What is UDP port 56183

We seen suspicious probing from source port 53 to destination port 56183. May I know what services use port 56183 (udp)?
2
votes
1answer
2k views

Nmap scan of iPhone public IP address shows port 21 open

I'm using my iPhone personal hotspot to connect to the internet on my computer via usb connection. I don't go through any other router or connection. The phone is my only means of connecting my ...
4
votes
1answer
562 views

General techniques for identifying an unknown service

I have a specific sample I'd like feedback on, but my view is an answer about general techniques is more valuable for this site. I'll leave the details in, in case anyone googling this bumped into the ...
1
vote
1answer
150 views

What security issues are there with remote access for firewalls, routers, etc.?

I am currently looking into cybersecurity for small businesses and it is something I have become very interested in. One of the questions in the questionnaire is: Confirm that any remote ...
1
vote
1answer
480 views

Running HTTPS service on port 443 [closed]

According to the Alexa Skills Documentation, I will get an unexpected communication issue if The endpoint is not configured to accept traffic over port 443. I'm trying to do this with my home router....
3
votes
1answer
1k views

Some explanation on Maimon Scan

I'm facing this question: When could the Maimon Scan be usefull? As I had no idea of what it was, I went into Nmap's manual and saw the explanation: The Maimon scan is named after its ...
0
votes
2answers
876 views

Bitdefender detected over a hundred port scans and still detects, what does that mean and what should I do?

I have Bitdefender Total Security 2017 installed on my computer and today especially in the last 10 minutes I got over a hundred port scans (detected and blocked) which is weird cause I usually get ...
1
vote
0answers
1k views

How do I access my webservice on port 443 using https? [closed]

I am trying to run a webservice via https on port 443 via self-signed certificate. Here is what I did first: Forwarded port 8080 Create self-signed certificate with openssl Add certificate to trusted ...
76
votes
9answers
20k views

Is it theoretically possible to deploy backdoors on ports higher than 65535?

Assuming you were able to modify the OS/firmware/device for server/client to send and listen on ports higher than 65535, could it be possible to plant a backdoor and have it listen on, say, port 70000?...
0
votes
1answer
2k views

GRC Shields Up test - are stealth ports good?

I used Steve Gibson's ShieldsUp test at https://www.grc.com. All Service Ports test says that everything is green (stealth) expect one blue (closed). I tried several times and one time, it gave me 2 ...
1
vote
0answers
575 views

Open Ports (WAN side) on Netgear R7000 Router using nmap

An nmap scan (WAN side) on my Netgear R7000 router indicates that there are two ports open: 80/tcp (http) and 1720/tcp (h323q931). My method to perform a WAN side scan on the router is to access the ...
0
votes
2answers
935 views

Are these Ports safe to have open?

I have a netgear router I recently hooked up to my other router provided by Xfinity(It sucks ass*). And I mostly use this router for my PS4 and Raspberry Pi because it just has a better wifi signal ...
0
votes
1answer
338 views

How to ensure if an SSH tunnling failed (if I haven't really tunneled)

I tunneled data transition as 22-22 and 2222-80, between my PC and VPS: ssh user@1.1.1.1 -L 22:localhost:22 -L 2222:localhost:80 -i ~/.ssh/key To make sure both tunnels were created, I executed lsof ...
1
vote
2answers
386 views

Tool to listen http traffic goes to different ports (Windows) [closed]

I am using a set of microservices (Spring MVC Hosted in Undertow containers along with Gradle) which are spawned on different ports in the same machine. Services make HTTP REST to each other. I need ...
2
votes
3answers
6k views

Does an open port with no service listening on it pose a risk? [duplicate]

I have a home server running Ubuntu 16.04 Server Edition. I have a couple ports that my router forwards to my server and ufw on my server allows so that I can access the services outside the LAN - ...
2
votes
1answer
235 views

Eavesdropping on a specific port of machine in the WLAN from a different machine, possible? (using arpspoof)

I'm using netcat -l 555 option to communicate between two computers(Linux) on port 555, is there any way I can eavesdrop to whats going on in that conversation from a 3rd computer? After the second ...
5
votes
2answers
5k views

Using Nmap to Scan Port Forwarding?

I have enabled port forwarding on my router to do some testing with Nmap. The internal IP address 10.0.0.10 on port 4245 is being sent to my public IP address on port 4245. I can access this with x.x....
-3
votes
2answers
766 views

Why is it a bad idea to allow all inbound / outbound traffic?

I have an AWS server. I didn't want to spend too much time configuring the Security Group and allowed all inbound and all outbound traffic. Is this OK or is it a bad idea?
0
votes
1answer
573 views

UPnP Open port on local device?

I ran Zenmap on a local IP address and found that it had one port running UPnP open and the guessed OS was a Windows distribution. Is this normal? Should I be concerned about it? In what ways could it ...
1
vote
1answer
1k views

Detecting Router (NAT) via port scan

I am developing a simple port scanner using Python, Scapy, nmap module. I want to detect if the host which I apply the port scan is a router or not. How can I identify or guess if the host is a router?...
0
votes
3answers
208 views

Using Nmap kicks me out my own network

I am working on a school task, where I have to use Nmap in order to scan for open port on another device on the same network. However, when I use Nmap my network suddenly gets limited. I have tried ...
0
votes
1answer
996 views

Bypassing closed or filtered ports

I recently setup a basic Ubuntu Server at my home and while at school can't access it because the SSH port (22) has been closed. This lead me open up different ports on my server for SSH so that I ...
1
vote
1answer
461 views

Is there anyway to probe open out ports?

I can use nmap to find open ports on a specific client with following command: nmap -sC -sV [IP] This command only shows incoming open ports, I'm looking for a similar command to find outgoing ...
1
vote
2answers
835 views

Port-Forwarding insecure? [closed]

I was going to do port-forwarding to create a gaming server with an old PC. I the found out that it makes more things visible to the internet. Is port-forwarding a bad choice considering its ...
0
votes
4answers
105 views

Is there any security flaw in using a non root port in production?

I am planning to use a web service running on port 8080 for serving some static files in production . Is it acceptable or is there any possible security flaw in this? NOTE- I don't want this service ...
0
votes
2answers
263 views

How to investigate open firewall ports further

I scanned my friend's firewall (Zyxel SBG3500-N) with NMAP and I found some undocumented ports open with services: 8888 tcp open http syn-ack lighttpd 1.4.34 18443 tcp open http syn-ack ...
1
vote
3answers
748 views

Spytechphone - iPhone

When port scanning my iPhone I get an RST, ACK from 'Spytechphone' over port 8192, does anyone know what this port does? I can't find any useful information. [1] http://www.iana.org/assignments/...
0
votes
2answers
751 views

Many Websites, one server, which port to use?

I've recently been doing some research on pentesting websites through metasploit. Now I've run into a problem that I'm sure is pretty common but I cant seem to find anything else about it on ...
1
vote
2answers
7k views

What purpose serve port 1900 in home router

Why would home router have port 1900/tcp (upnp) open? What kind of purpose would that serve for the operator (service provider)? I searched info about it and found this an article saying: Security ...
1
vote
2answers
300 views

Determining source port

Working on a project where I have to determine the source TCP port used for an executable program (Meaning, when the program is running, what TCP port would it use to connect to the remote location). ...
0
votes
2answers
89 views

Compromised server name and port number of a SQL Server DB Server

I would like to get an expert opinion on how dangerous is it to have the database server name and SQL server instance and port number compromised by accidentally exposing it in source code snippet ...
4
votes
1answer
323 views

My home modem-router is occupying most subnets

I was port scanning my own isp-issued modem-router and stumbled upon something unsettling: looks like it is listening on ports 554, 7070 & 1863 on (almost) every ip of this interval: 192.168.0-255....
1
vote
1answer
2k views

Why is my Windows 10 machine listening for 127.127.127.127:3939?

I was hoping someone out there could answer why my Windows 10 Machine would be listening on port 3939 using 127.127.127.127 over TCP? I get the below with netstat -nat: TCP 127.127.127.127:3939 ...
0
votes
1answer
212 views

How to get any information from 1102,1104,1105,1106 ports?

I have port output from nmap scan below. 1102/tcp open ssl/adobeserver-1? 1104/tcp open ssl/xrl? 1105/tcp open ssl/ftranhc? 1106/tcp open ssl/isoipsigport-1? ...
1
vote
1answer
35 views

Communication between infected machines via listening to certain port

Are there any detailed case-studies in which infected machines in a certain network or on the internet were communication with each other (I'm not interested in cases with only machine <-> C&C ...
1
vote
3answers
920 views

MySQL 3306 open port security

I know that having the MySQL 3306 port is unsafe even if you restrict the user access based on IP. But what if you really need remote access to your database ? Maybe two applications reading and ...
2
votes
2answers
1k views

What can be a reason you DONT want to use port 443 for SSL communications

I have a very open question which I dont know if it's allowed but I am so curious about any possible answer. We are trying to make a connection to a other service for my company and the webservice ...
-1
votes
1answer
574 views

Get Services On Open Port

Is it possible to get a list of services running on an open port? E.g. I am connected to port 80 with netcat and I want to get services that are listening.
28
votes
9answers
15k views

Is it safer to use a port other than 21 for FTP?

Usually (as far as I know), FTP uses port 21. Since this port is used for FTP so often, is it safer to use another port? My guess is that if someone with malicious intentions tries to break FTP ...
0
votes
2answers
2k views

Why isn't FTPS, SFTP, or other protocols which use SSL/SSH on port 443/22?

ANSWER ON THE BOTTOM I'm in the process of taking my Security+ exam, and I was taught by the professor teaching me that, when trying to figure out what port to put a protocol on (as there are a LOT ...
2
votes
1answer
205 views

Dealing with “trojan” ports

We have a SOC which "monitors" our network activity, it basically collects all logs from all our firewalls and creates reports. We have a huge network with hundreds of servers and upto 2000 users, ...
27
votes
1answer
4k views

Why is it better to use ports 20 and 53 as source ports when portscanning?

I read that if a server is inside a DMZ behind a stateless firewall, it is a good idea to use ports 20 and 53 as source ports when conducting port scanning. Why is this a good idea? I guess the ...
0
votes
2answers
390 views

Wondering about open port found while using VPN service

I have noticed during port scanning that my "anonymous" IP has an open port (111) while I am using VPN. Does this make me vulnerable as user or is it the provider's failure? Should I change ...
2
votes
3answers
4k views

Can nmap take a list of ports to scan from a file?

Nmap can take a file containing a list of hosts to scan using the -iL flag. Is there similar functionality for a file containing a list of port numbers? I've scoured the man page, online docs at nmap....
3
votes
0answers
493 views

What vulnerabilities are associated with port triggering?

Background To address a VoIP voice lag issue, my provider added port triggering rules for over 42,000 ports on my router, which seemed sloppy. And as I understand it, port triggering should only be ...
0
votes
1answer
867 views

How can all ports be closed? [closed]

I was faced that, there was an hacker attacking my gmail account. With the help of google service, I got the information about that hacker. Again next day he was attacking my pc. When I scanned ...
-1
votes
2answers
5k views

Kali Linux/Metasploit in VirtualBox - Issue with ports

I've been attempting to get port 4444 to open these past couple of days. I finally figured I'd try to get it working on my Windows machine first and I finally got it. Now, no matter what I do in the ...
3
votes
3answers
7k views

Is QUIC (Quick UDP Internet Connections) safe to allow through firewall?

Our firewall currently blocks QUIC (UDP 443) traffic which seems to be enabled by default in Google Chrome. Is it safe to allow QUIC or should I wait until it is implemented in all the major browsers? ...
5
votes
2answers
1k views

Samba open ports, not being filtered

nmap scan of my ubuntu computer, output when ran with -sV: 139/tcp open netbios-ssn Samba smbd 3.X (workgroup: MEDIAPC) 445/tcp open netbios-ssn Samba smbd 3.X (workgroup: MEDIAPC)...
1
vote
3answers
9k views

What can I do about being heavily port scanned?

I have two devices connected wirelessly to my Linksys router while running Symantec Endpoint Protection on my computer. A few days ago I started using the internet by connecting the cable directly to ...