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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
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3answers
98 views

2 vs 3 tier network architecture

I am interested in how a 3-tier network topology (web/app/data) provides improved security than a 2-tier topology (web-app/data). I understand the concept of a DMZ as the initial contact point with ...
8
votes
2answers
15k views

Is opening both TCP/UDP less secured than just TCP or UDP when needed and why?

If application needs opened port X UDP, or X TCP combination. Is there any potential risk by opening both UDP/TCP as I usually am not sure which one the application uses?
0
votes
1answer
69 views

Is there a software that would scan the ports automatically, then predict if there are any malicious activity going on, on my Win10 PC? [closed]

I've got this malware(or spyware as Kaspersky detected), from the USB storage device by purely a lack of focus. After scanning and defecting all the drives that are connected to my computer with ...
1
vote
1answer
514 views

What are the possible solution for blocking VPN connection on a home network?

I am not a techie. I am just wanting to force some parentral control using OPENDNS. Opendns works fine however it is easily broken on android or windows using vpn software like ultrasurf or latern or ...
-1
votes
1answer
67 views

How to find out which application runs behind port 31337?

I found an open port on a "Kartina Quattro" (https://www.kartina.tv/article/247-kartina-quattro). It's a device for watching russian TV channels. The port number is 31337 and the Service is called ...
3
votes
1answer
412 views

Ports Showing Closed/Filtered in Nmap Scans

hopefully this isn't a stupid question.. I am running some nmap scans and I get a list of ports that show closed. Why would they even show in the scan report? Can these be exploited further with other ...
0
votes
2answers
105 views

Does having Frontend and Backend on the same port any consequences?

I am currently working on a mean application, with an Angular frontend and an express/node backend. Frontend and backend communicate together with a REST API. When I deploy the application, both the ...
0
votes
1answer
86 views

Detecting port scanning activity of a mobile app

I highly suspect that one of my iPhone apps is scanning for open ports on the local network, but can't think of a way to detect such activity. I know that I can monitor http(s) connections by using ...
1
vote
1answer
90 views

What ports are okay to be open on a macbook pro?

When I do a network scan for open ports on my MacBook Pro, I can see the following open TCP ports below. Are these 'standard' open port for a personal computer of this type? Should I be concerned? ...
6
votes
6answers
28k views

Exploiting through a filtered port

I'm doing some pentesting against a machine the lecturer set up in the lab. NMAP shows port 445 to be filtered and Nessus confirms the ms08_067 vulnerability is present on that machine. I tried ...
0
votes
2answers
104 views

Open ports on my NetGear router

I ran an nmap scan on my home router and I am seeing a ton of open ports. Is this normal? How do I go about closing them? $ nmap 192.168.1.1 Starting Nmap 7.70 ( https://nmap.org ) at 2019-03-16 20:...
1
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0answers
26 views

Nmap showing different open ports every few seconds [duplicate]

I'm running Nmap on an Amazon Web Services EC2 instance but between runs just a couple seconds apart, I'm getting new results. Is this normal? I'm seeing open ports then they don't show. I'm running ...
1
vote
2answers
6k views

Can a hacker hack into port 80?

We normally say port 80 is firewall friendly. But can a hacker just hack into port 80 via TCP or UDP? Or is Port 80 by default not always open? It waits for the host to initiate a connection via ...
1
vote
1answer
62 views

Determine victim of port scan's OS

I am taking part in a practice sandbox, and have a pcap file in Wireshark: with the traffic depicting a Vertical Port Scan. Is there anyway to find out the "victim"'s Operating System? The packets are ...
7
votes
1answer
4k views

What are non-standard ports and protocols [closed]

I am new to the security field and reading about how to check if an application is secure. One of the checks involves finding out if the app uses non-standard security ports and protocols. However, ...
5
votes
3answers
2k views

Why would a stealth scan attract more attention than a connect scan?

I'm reading an Information Security book and am faced with the question: Why may nmap stealth scans(SYN) attract more attention than simple connect scans(TCP connect())? Why might it be?
0
votes
2answers
161 views

Do I lose the anonymity of a VPN if they open a port for me?

I currently use a VPN supplier that does not allow for opening ports. They argue that I lose the whole point of a VPN and the anonymity by doing this. I can't see how and they don't seem to be able to ...
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? ...
-1
votes
1answer
142 views

TCP Scans vs SYN Scans in port scanning

What is the difference between TCP Scans and SYN Scans?
0
votes
0answers
24 views

Finding how many filtered ports of a host that would be listed as “filtered” on Nmap

I just started working on nmap and was confused by this question. I'm unsure if I understood it correctly, so I appreciate your help with this. Using Nmap, find how many ports are filtered in testphp....
4
votes
2answers
286 views

Is is bad practice to use non-standard ports? (for example ssh from 22 to something different)

Background is that I am learning some technical stuff with the Enki App. In this case about security. The App states that it is a misuse of a port if I change for example the ssh port from 22 to ...
1
vote
2answers
110 views

Should ports be visible to nmap?

I'm currently working on the firewall when I discovered that the firewall exposes a lot of ports outside of the internal network. I discovered this when setting up a new FTP server using a basic nmap ...
0
votes
2answers
751 views

can a backdoor executable be used on an occupied port?

Suppose I am doing a penetration test on a network that has a firewall that blocks all ports except 80, 110, and 443. I want to use a metasploit reverse-TCP backdoor executable written in msfpayload ...
4
votes
3answers
6k views

Setup of Kali Linux for reverse shell connections over the internet

I am running Kali Linux as a VM on my Windows machine which is NAT'd behind my company network, if I wish to pen test a website for a client and believe that a reverse shell is possible, what is a ...
1
vote
1answer
144 views

Understanding port scanning with firewall enabled

My objective is to do a port scanner in windows and find the ports which are open. Suppose, I run an application which opens up a port 8000. Now I create a new inbound rule to block all incoming ...
45
votes
5answers
14k views

Should I close port 80 forever and ever since the 2018 Google-indicated web-security initiatives?

I often establish Ubuntu-LAMP environments on which I host a few Drupal web applications that I myself own (I don't provide any hosting services and never done so in the past). Whenever I establish ...
1
vote
2answers
1k views

OSSEC, what is it telling me about port changes?

I've been diving into OSSEC for the last couple of months, but I feel unclear on one of it's alerts. I've provided the alert below. The main difference I see in previous output and current output is ...
1
vote
3answers
736 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/...
2
votes
1answer
57 views

Is it safe to have port 443 unprotected by firewall without application?

Say I have a website, http://www.mostlysecuresite.com, which runs on a server at my house. Let's say I wanted to get an SSL cert in a few weeks. Because of this, I had my Port 443 forwarded on my ...
1
vote
2answers
92 views

Port bound TLS certificates? (1 Self-signed & 1 CA)

For my android game, I want to secure the connection between the server and its clients through TLS certificates on each side, because of the sensitive data that is beeing exchanged through a token ...
0
votes
2answers
317 views

Do I have to block UDP ports when I launch my own server with a public IP?

I am trying to give better security to my Raspberry sever. When I installed UFW, I allowed just port 80/tcp and my own high port for SSH communication, and by default are all others ports "deny". ...
20
votes
6answers
29k views

Why do hackers scan for open ports?

So, whenever you hear of the mean little hackers who hack websites you hear of "port scanning". I understand what it is (looking for all open ports / services on a remote machine), however that begs ...
1
vote
1answer
28 views

Why do processes on servers have socket types associated to the port number? [closed]

Why do some servers have TCP/UDP alongside the port they're listening to. To my understanding TCP and UDP are socket layers, they're methods of determining how the traffic is being sent over the ...
0
votes
1answer
1k views

Strange devices & open ports on my network

I have performed several Nmap scans on my network to determine what devices are connected and which ports are open. To my surprise I found a very strange device connected(which I do not know ...
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 ...
0
votes
3answers
2k views

Port sweep vs port scan

I was asked this question in an interview: "What is a port sweep?" When I replied with port scan he said that my answer was not a scan, it was a port sweep. I googled and found "tcp sweep: but not "...
1
vote
1answer
252 views

NMAP reporting all ports open

I'm trying to scan my targets for open ports. However, NMAP reports all of them as 'open'. I know there's a firewall in between. I tried the SYN scan, and when I check the traffic in WireShark I see ...
0
votes
3answers
203 views

Nmap scanning single port too fast? Shows as filtered?

I ran into an issue when trying to scan a single port on a single machine. I ran a range scan to find machines with port 25 open. Then I just arbitrarily chose one to work on. I scan that machine with ...
8
votes
1answer
4k views

Connection to ports 2000 and 5060 successful despite filtering

I run my own (Ubuntu based) router and have iptables configured to drop all incoming packets by default. To my surprise, running an nmap scan (from the WAN side) shows two open ports related to VOIP: ...
-1
votes
1answer
81 views

Port knocking is authentication?

In computer networking, port knocking is a method of externally opening ports on a firewall by generating a connection attempt on a set of prespecified closed ports. Once a correct sequence of ...
0
votes
2answers
518 views

Multiple Open ports on a server, is that safe? [closed]

Using nmap I try to scan a server as a result I get multiple open ports. For example when I try to scan domain.com as a result: 7/tcp open echo 9/tcp open discard 13/tcp open daytime 21/tcp filtered ...
0
votes
1answer
53 views

What is an excessive amount of SYN requests for port scanning?

I have a slow internet connection - about 12Mb/s. In 10 minutes I have detected a distributed port scan on the router from different IPs. I have counted these SYN packets at in 600 seconds (10 minutes ...
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
1k views

NMap scan from within armitage - missing root privileges

I just installed metasploit + armitage on my Ubuntu 16.04 machine. When I start armitage and click "Hosts->Nmap->Quick Scan (OSdetect)" I get the following error: msf > db_nmap --min-hostgroup 96 -...
0
votes
1answer
321 views

Why adclick.g.doubleclick.net listens on all ports [closed]

I have adclick.g.doubleclick.net listening on all ports. When I launch an application like Starcraft 2, for example, it is listening on localhost. Or for some applications, there was a connection from ...
1
vote
2answers
47 views

Is there a point to set up passwords for services like MySQL, Redis etc. if we disable their related ports?

Redis' default port is 6379 and MySQL's default port is 3306. Let's say we disable these ports to outside of the world with ufw. And let's say only I have access to the servers. Is there still a point ...
0
votes
1answer
270 views

Are there open by default ports with Centos 7's firewalld?

My Centos7 firewalld has TCP ports 8083, 8086, and 5000 open. I don't recall opening them, except for maybe 5000 when first learning about firewalld. Are there any ports that might come out of the ...
-1
votes
1answer
137 views

What ports can make me get RCE on the devices? [closed]

I know that remote code execution depends on the service running on the open port. For example I know that SSH, FTP may be vulnerable to RCE if they are running an unpatched version. So what about ...
-1
votes
1answer
99 views

Does Windows perform TCP and/or UDP port scans? [closed]

I want to know whether Windows Operating System does TCP/UDP port scans, and how often if it does? Thanks for your time.
1
vote
1answer
82 views

Refusal to 'open' up corporate network?

I am working a project which requires access to a service running on a remote server, over a single TCP port (>1024). This service runs on a machine located within an existing network, and the project ...