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Questions tagged [firewalls]

Concerned with software or hardware firewalls

2
votes
3answers
3k views

Large amount of foreign IPs hitting out firewall, is this automated scans or are we under attack?

I just got put in charge of a network. In the logs on our firewall I noticed that we had a large amounts of machines trying to connect to port 53 as well as about a dozen other ports. Are these ...
0
votes
0answers
13 views

IPv6 firewall problem with ps4 [migrated]

I'm experiencing a problem with my router cisco d3928 and codww2 online. I opened all the ports needed to play codww2 online and nothing worked, but if i disable ipv6 firewall i can play normally. ...
1
vote
0answers
42 views

Weak ciphers in TLS VPN

We have a firewall out of our firm network and administrators connect to this firewall by VPN over TLS. Scanning this firewall, the vulnerability scanner get us some warning as the 443 port allow weak ...
-1
votes
1answer
45 views

How do I open port 443 or HTTPS in Windows Server and Ubuntu Server? [on hold]

I am trying to open port 443 on Windows Server 2012 R2 and Ubuntu Server 18.04. I am scanning both of these in zenmap to see if port 443 is opened and it is closed on both of them. I would like for it ...
3
votes
1answer
54 views

Block Outbound Connections by Country

We want to reduce the number of phishing sites that our users can get to. Would it be useful or more problematic to block outbound connections by geo IP? We already block many inbound connections by ...
0
votes
1answer
40 views

Can Snort or Suricata *edit* packet on the fly?

I know that they can detect traffic by rules, but can they modify packets on the go? For example, not only detecting HTTP GET but also adding headers to the GET packet. If they can't, is there an ...
3
votes
3answers
6k 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
vote
1answer
73 views

Fortigate Creating Millions of DNS events to standard domains

I am trying to tune our SIEM and noticed that we are receiving millions of DNS records every day from the same domains. These are: update.microsoft.com swscan.apple.com softwareupdate.vmware.com ...
2
votes
0answers
32 views

Beginner UFW question about destination any

I'm learning about UFW with a Raspberry Pi and I don't a couple of things when it comes to UFW rules. Can anyone help me suss a couple things out? My first question is about the destination any. If I ...
22
votes
4answers
76k views

Windows Firewall - how to block inbound for all .exe files in a folder

In Windows Firewall with Advanced Settings I can create a rule which blocks all inbound or outbound traffic for particular program by pointing to its .exe file. The problem is that this program has ...
1
vote
1answer
20 views

Providing access to Git repo behind a Firewall using Certs/Keys for Authentication

We have git repo sitting behind a firewall. As I see, there are two ways of authenticating/accessing the git repo Add a Reverse HTTP Proxy in the DMZ that communicates with the git repo. This will ...
0
votes
1answer
18 views

In what situations / with what nodes should a node ping / not ping?

I was recently looking at a network in which the client-machines that accessed a webservice endpoint, but which could not ping the webservice endpoint. And there are other machines that can ping the ...
0
votes
0answers
68 views

Filter/Block OpenVPN clients' access to a specific website

As stated in the title I would like to restrict VPN clients' access to specific websites. More specifically, I push the route for 5 websites to the clients via the server config. However, I would ...
0
votes
2answers
91 views

Why should I bother having a firewall on servers?

In the case of a server, the only applications that are running there are the ones that I've setup, so you don't just have random users downloading & running malware. The only ports that are open ...
0
votes
1answer
251 views

Ability to get a MAC address and IPv6 through proxy servers

Now I'm pretty sure I know the answer to this question, but I am just curious to see what the security experts of the world think of this. First a little back story: I was a former member of a ...
23
votes
7answers
3k views

How can I publish data from a private network without adding a bidirectional link to another network

I was just wondering how I could build a private network where it is physically impossible to gain access from outside but still have the option to publish data to some remote server. As an example: ...
0
votes
1answer
74 views

Country Blocking

I use a Meraki firewall and want to block outside attack attempts. Is there a list of countries that are known to be malicious? I want to load them into the system and GEO block them. I know that some ...
0
votes
1answer
62 views

Types of firewalls to implement to reduce DoS attacks in POS systems

Would you need an internal, external and a host-resident firewall for each POS client?
0
votes
1answer
70 views

Secure onion router setup [closed]

I would like to setup a Raspberry Pi as an onion router, but I have some questions about it. At home I am using a Fritz!Box to connect to the outer world (to the net of my ISP). Would it make any ...
0
votes
0answers
43 views

PHP socks proxy with no port opening

let's say i have file apache file access on a webserver, but due to firewall rules etc, i can't connect to ssh and can't open a port. Is there a way to do this exactly this : create a socks proxy on ...
0
votes
1answer
281 views

Why won't ossec block SSH connections when it seems to be configured correctly?

Why won't ossec block connections from another server? I installed ossec version 2.9.3 on Ubuntu 16.04. In the ossec.conf file I have these lines where x.x.x.x is the IP address of a second Linux ...
0
votes
1answer
140 views

Differentiating between IKEv2 and OpenVPN Traffic

There is a WiFi network that I regularly use, and it seems to be blocking all VPN traffic other than IKEv2. I tested this by downloading many of the free/freemium VPN apps from the Google Play Store ...
0
votes
0answers
12 views

Why Does Windows Server Block ICMP By Default? [duplicate]

I am conducting a OpenVAS vulnerability scan on a Windows Server 2012 box and it came back empty. It turns out that the scanner checks to see if the host is alive by sending it a ping request--if it ...
0
votes
0answers
29 views

Distributed network with one host behind dmz and the other without

Context: This a question from my homework assignment. There is a company with two sites A and B. B is behind DMZ (firewall - proxy mail server - firewall) and A is just behind a firewall Network A ...
0
votes
2answers
711 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 ...
0
votes
1answer
33 views

IPsec down with unusual SNMP traffic [closed]

Time to time IPSec tunnel status become down, with unusual SNMP Traffic. when I disable and enable port manually, it become normal. I am using 200E fortigate firewall. Have you any idea or previous ...
4
votes
2answers
3k views

Is it dangerous to disable the IPv6 firewall built into many home routers?

The router that my ISP has delivered contains an IPv6 firewall. The only configuration option is whether it is on or off. Apparently, this firewall simply denies all incoming connections. I ...
0
votes
2answers
95 views

What is the thought process behind, Endpoint protection is better than firewalls?

I keep reading about, and seeing people post and recommend in the oddest places, that strong endpoint protection is better than having a in-service/supported/receiving security updates firewall. What ...
1
vote
1answer
73 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 ...
1
vote
2answers
3k 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 ...
3
votes
3answers
238 views

Web Application Firewall using web app source code analysis

I read this page: Category:OWASP Best Practices: Use of Web Application Firewalls, and I found that WAF cannot generally detect logical attacks. We know each web application has a number of input ...
-1
votes
1answer
102 views

How to safely expose a computer to the Internet with a public IP

Our LAN is configured behind a load balancing router, in turn connected to a modem assigning public IPs to connected devices. I am required to randomly test the connection effective throughput, ...
20
votes
7answers
86k views

How to bypass tcpwrapped with nmap scan

I'd a scan task and I faced following result Host is up (0.032s latency). Scanned at 2012-10-25 16:06:38 AST for 856s PORT STATE SERVICE VERSION 1/tcp open tcpwrapped 3/tcp open ...
0
votes
1answer
64 views

How do I configure a home router to block traffic to and from specific geographic regions? [closed]

My mom keeps typing in wrong URLs with typos and getting sent to Chinese typosquatting malware or fraud sites, so I want to configure my home router to block all traffic to and from China as much as ...
55
votes
10answers
106k views

Why block outgoing network traffic with a firewall?

In terms of a home network, is there any reason to set up a router firewall so that all outgoing ports are blocked, and then open specific ports for things such as HTTP, HTTPS, etc. Given that every ...
2
votes
2answers
8k views

How to block network scans with pfsense?

I am using pfsense as a firewall, and I would like to know how I can stop network scans from enumerating open services and ports.
29
votes
3answers
7k views

Is it practical to pre-blacklist certain GeoIP regions?

In recent events, a server I've been managing with has been under a few attacks, a risk you take when hosting a web-server. The firewall has been set up properly to only allow connections through the ...
1
vote
1answer
111 views

Do I need two firewalls or is one enough?

We have a bunch of company devices (servers, desktops, laptops, company-issue phones, etc). All of these devices are company devices, every employee uses them just for business. All devices should ...
22
votes
1answer
6k views

What is a Web Application Firewall?

What is a Web Application Firewall (WAF) and what are some of the things to look for in an effective one? Why would you deploy a WAF instead of just an IPS?
0
votes
2answers
157 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". ...
12
votes
1answer
22k views

Is it safe to disable connection tracking in iptables?

While reading about NOTRACK target of raw table in iptables, I encountered an article suggesting that for certain traffic you could (or even should) disable connection tracking. The two examples were: ...
3
votes
1answer
109 views

Firewall Showing 1,000's Of Strange GET Parameters Being Sent To Login Page?

So I woke up today, and checked my Firewall Events on CloudFlare for my website like I do normally. Most of the time I'll just see thousands of failed SQL injection attempts, but this morning I was ...
3
votes
3answers
1k views

How can someone access my computer (“hack me”) when my firewall is off?

Why do people go crazy when the firewall if off? Most sites on the internet say its very dangerous to turn off your firewall and I want to understand why. For example Microsoft says this: You ...
1
vote
0answers
36 views

health check to test haproxy — request deny with 200. good idea?

I have been working on a multi-provider redundant load balancing solution using HAProxy, AWS, and Cloudflare. I have a solution, and I believe it will be secure, but I am looking for further ...
3
votes
0answers
140 views

How can Nmap bypass Windows Server firewall rules?

I need to block all communication (inbound/outbound) from server A to server B (all ports/all protocols). Server A should communicate with every machine except server B. I can't place firewall rules ...
0
votes
1answer
41 views

Telling the difference between firewall block or external problem with Page Cannot be Displayed (IE) [closed]

In our organization, when users run up against the firewall in Internet Explorer, this is what they see: The classic IE "Page Cannot Be Displayed". Of course, this is also what you see when it's ...
-1
votes
1answer
42 views

Infection of malware

Lets say, My firewall is configured to block any incoming connections My browser doesnt allow any traces and scripts I have vpn on My browser always asks before downloading files My browser doesn't ...
1
vote
0answers
53 views

UFW (Uncomplicated Firewall) Question

I was wondering if there's any benefit of adding following rules to a Raspberry-Pi directly exposed to the internet: sudo ufw deny to 0.0.0.0/8 && sudo ufw deny to 169.254.0.0/16 && ...
2
votes
2answers
127 views

How are stateless firewalls useful in public cloud platforms?

I'm trying to understand the value of stateless firewalls in public cloud platforms like Network Access Control Lists (NACL) in Amazon Web Services (AWS). I think I know a few ways I can use them, but ...
0
votes
1answer
232 views

IDS and IPS placement in network? [duplicate]

What is the good practice for the placement of IDS (NIDS) and IPS? Before the firewall or after the firewall? and why?