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Questions tagged [firewalls]

Concerned with software or hardware firewalls

1
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1answer
441 views

Creating a secure home network - Which firmware should I use and how should I configure my firewall?

I am starting to take on more and more enterprise clients while working remotely from my home office. I have a pretty secure network at the moment, but I have a lot hardware that I am not using and ...
0
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1answer
75 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?
8
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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?
1
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1answer
69 views

Separation of devices for VPN / Firewall [on hold]

Our company has two separate firewall devices from different vendors (Checkpoint / Cisco) for firewall and VPN access. We're currently evaluating the possibility of migrating to a newer, clustered ...
4
votes
2answers
2k views

how can an attacker access a system through a compromised router?

Let's say an attacker gained access to the admin panel of a home router with port 21, 23 and 80 open. I mean the attacker has full control over the router, thus being able to port forward, etc... ...
-2
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0answers
40 views

How are Web application firewalls typically implemented?

How are WAFs typically implemented? I'm currently doing some research on this topic and found some sources that claim their ".htaccess" rules are used as a WAF. Q1: I was wondering if this method ...
0
votes
1answer
357 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
73 views

Block a file from being accessed over the internet

I keep my client data in a password protected Excel file. For added security, I would like to block access to this file from potential hackers on the Internet. Is it possible to block access to a ...
0
votes
1answer
230 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
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0answers
34 views

Why is Zone Alarm Blocking VMWare Virtual Network Editor?

I have version 15 of VMWare running on my Windows 10 computer. When I open the Virtual Network Editor and try to add a bridged connection, I get an error saying: Cannot change network to bridged: ...
0
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0answers
27 views

standards reference to perimeter security

I have the following problematic that I am currently dealing with. I have two zones/perimeters that need to be interconnected, some standards protocols have to be whitelisted such as HTTP, FTP, SSH ...
0
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0answers
5 views

Microsoft Telemetry Data [migrated]

I work at a large company and started digging through firewall logs to get my head around the network and what is going on. I noticed a HUGE amount of traffic going to 72.21.81.240. I cross-correlated ...
0
votes
2answers
124 views

Security measures to take upon acquiring a new laptop?

I'm planning on buying a regular HP laptop. However, I'm still a novice when it comes to information security. I'm planning on using this laptop to SOLELY login to my bank accounts and NO OTHER ...
24
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9answers
27k views

How important is NAT as a security layer?

I've signed on to help a department move buildings and upgrade their dated infrastructure. This department has about 40 employees, 25 desktops, an old Novell server, and a handful of laboratory ...
0
votes
4answers
289 views

Is it a bad idea using two firewalls on the same PC?

If i'm using windows default firewall and a third-party firewall, is it represents a security issue or I have to worry just with possible conflicts? And what type of conflicts could exists?
5
votes
3answers
1k views

What is the difference between an anti-virus and an IPS?

As I understand it, an intrusion protection system (IPS) detects anomalous behavior, does detection of protocol anomalies, and does signature filtering that blocks malware, DDoS, etc. An antivirus ...
4
votes
2answers
2k views

Benefits of home router behind Linux firewall?

Like a lot of people I have a simple consumer grade router at home. The setup is pretty standard: Ethernet from the cable modem --> router's WAN Given the poor track record of consumer routers ...
0
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2answers
83 views

Security of next generation firewall

In recent years there's been a number of IndieGoGo or KickStarter projects for smart device protection, or next-generation firewalls. Some examples are: Anonabox, Cujo, Dojo, Firewalla, Keezel, ...
1
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2answers
85 views

How does TLS traffic impact firewalls?

If I have an open port on a firewall it means that I can receive traffic on that port. If it's unencrypted I assume that the raw data is just allowed through. If TLS is being used, does firewall ...
5
votes
3answers
468 views

What are the security implications of allowing unlimited size cookies?

Our application firewall blocks requests if it detects a cookie is present with a value greater than 1024 characters in size. Are there any exploits involving large cookies? i.e. How much more ...
0
votes
1answer
42 views

Network diagram based on Cisco ACL and other firewall rules [closed]

Are there any tools for automated building network diagram from ACL rules or any other firewall rules?
3
votes
1answer
401 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 ...
1
vote
1answer
97 views
3
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3answers
264 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 ...
4
votes
3answers
538 views

The safest way to circumventing Iran's Internet censorship

We usually buy services like VPN, SOCKS, Kerio [Kerio Connect?]... to circumvent Iran's Internet censorship policy. Recently, one of the shops started selling [one of] Kerio's products, for which I do ...
1
vote
1answer
99 views

Why would my firewall be blocking external source and external destination IP's that I dont own? [closed]

In my Cisco ASA firewall logs I'm seeing events being blocked with an external source IP and a external destination IP. This is happening in the same event log. An example would be: TCP access ...
3
votes
1answer
47 views

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

We have a Git repo sitting behind a firewall. As I see it, 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 ...
1
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2answers
163 views

Firewalls vs DMZ

What's the difference between Firewalls and DMZs? These terms seem to overlap at time and I'm not clear on the difference. Maybe a DMZ is achieved using firewalls?
7
votes
1answer
20k views

How do I access a firewall log (Windows 10 w. Windows Defender)

I am going through some event logs (in event viewer), and noticed I can't seem to find any firewall logs. Windows Defender provides the firewall. How do I get to the firewall logs that should be ...
0
votes
1answer
41 views

Are there any alternative methods for reverse connections that bypass firewalls?

I'm doing a PenTest on a server. I have an RCE vulnerability on it, but when I try to do a reverse connection via netcat, the firewall blocks it. Is there any other methods used for reverse ...
0
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0answers
50 views

Stopping “phone home” applications in VM with TBB

I have a VM with Linux and the TBB installed on it. What I am trying to do is to make sure that other applications like for example operating system applications cannot "phone home" while I am using ...
-1
votes
1answer
101 views

Detecting and blocking TCP VPN connections that bypasses existing VPN detection software

I help manage a small college campus network and students are not allowed to visit certain sites and download using torrents. Currently I'm able to block UDP VPN connections, but TCP VPN connections ...
2
votes
2answers
192 views

How do the CVE-2018-10562 and CVE-2018-10561 exploits work?

https://www.vpnmentor.com/blog/critical-vulnerability-gpon-router/ Firstly, the use of 'GPON' I find misleading because this vulnerability is to do with the routers and webservers and not the access ...
0
votes
0answers
47 views

Windows Firewall blocking local access to SQL Server?

I have an AWS virtual machine running a web application on IIS that connects to a SQL Server database (on the same machine). Recently, I have noticed that there are a plethora of failed login attempts ...
0
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0answers
53 views

Windows Firewall - How do I know that I have completely blocked a program?

I have a specific software that I cannot let out to the internet but it is crucial that it has access to the local network. I can create an inbound and an outbound Block rule for the main application'...
1
vote
0answers
52 views

OpenAppID with Snort on pfSense [closed]

I'm using OpenAppID with Snort on pfSense, it actually work but when I view some script detector, it just detect by http pattern, which I can replace by using snort rule (with "content" option). So ...
0
votes
1answer
409 views

Is it advisable to accept STUN server connections?

My firewall reports outgoing connection attempts via com.apple.WebKit.Networking to a number of STUN servers (namely, stun.nas.net, stun.node4.co.uk, stun.voxox.com and stun.wwdl.net). This is ...
0
votes
1answer
115 views

Difference between a behaviour-based security and traditional firewall?

Difference between a behaviour-based security and traditional firewall? As I have searched the web and honestly cannot find anything about it.
27
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7answers
93k 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 ...
1
vote
3answers
572 views

Windows firewall blocking of a dynamically generated .exe

If I block application A.exe on my firewall, but it dynamically generates B.exe and runs it automatically. Would B.exe also be blocked on my firewall?
7
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2answers
1k views

I'm having a DDoS attack, my hosting company is not giving me a solution, and I need to know what is hapening

So ok, right now my windows 2003 dedicated server is under attack by some guy who's flooding UDP packets (~90.000 packets/sec) on my 100Mbps server for the last 8 hours. I'm on a shared port, so I'm ...
0
votes
1answer
24 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 ...
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 ...
3
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 ...
1
vote
0answers
62 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 ...
3
votes
1answer
67 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
70 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
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
vote
1answer
83 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
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0answers
33 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 ...