Concerned with software or hardware firewalls

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Is Windows Firewall suitable for running in a production environment?

Is Windows Firewall suitable for running as the sole protection on a production web server? Is it hardened enough? Robust enough? and tested enough? I'm running a VPS with Rackspace on their cloud ...
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3answers
4k views

How do I configure nmap to verify my firewall is performing stateful packet inspection?

As part of a compliance audit, I need to run a routine scan that verifies that our firewalls are performing stateful packet inspection on incoming packets. I have a dedicated server outside our ...
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4answers
5k views

HTTPS firewall rule

Setting up Firewall rule for HTTPS websites on basic stateless packet filter firewall This seems like a stupid question, but how do I set up a firewall rule to allow HTTPS on a basic packet filter ...
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3answers
342 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 ...
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Which of these ports are safe to leave open, which are not?

I just ran nMap against my IP address and got the following result: PORT STATE SERVICE 21/tcp open ftp 22/tcp open ssh 23/tcp open telnet 80/tcp open http 443/tcp open https ...
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614 views

Why are simple packet filter firewalls insufficient for the protection of web applications?

I was wondering why exactly are simple packet filter firewalls insufficient for the protection of web applications?
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1answer
464 views

How did my homepage get changed in IE?

I have rarely used IE in the past. I just use it to test how a website looks. Today all of a sudden when I went on to open IE, it opened with a homepage that wasn't set by me. It was an address of a ...
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9k views

How do you properly setup Tor on Windows 7?

How do you properly setup Tor on a Windows 7 box to guarantee that ALL connections will run through Tor?
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1answer
6k views

Fail2Ban does not ban failed root login attempt

I have a small server which only open ports are ssh, http and https. I have fail2ban installed and set up so that after 3 failed attempts someone gets blocked for 10 minutes (thats the dafault I ...
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2answers
558 views

Firewall design for big enterprise business

I am wondering if there is any best practice firewalling rules that should be put in effect in most modern networks. For example should the network atleast have the following firewall zones? Client ...
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1answer
379 views

Exploited by newbie3viLc063s

My debian server got exploited by some scriptiekiddie who used Newbie3viLc063 http://pastebin.com/jma8JRG1 . Scriptkiddie uploaded logo_php.png to my server (My permissions sucked :s) and he did run ...
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Is it really better to use port 80 or 443 for outgoing traffic in order to bypass user firewall?

I recently created a reverse connection shell in C#. I tested it with some computers and I noticed that some computers connected back correctly and I established connection with them but another ...
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297 views

Placing a firewall—without creating a new subnetwork

I have a couple of networks that have multiple IP addresses, and where I have absolutely no choice as to the equipment used for the network's edge router (the device that connects both to the LAN and ...
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2answers
52 views

monitor port scan on the same segment

if theres a port scan on the same segment and it does not reach the firewall at all, it is not detectable by anything. is there any solution to that ? maybe using the windows fw on ach workstation to ...
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3k views

Docker port forwarding exposure

I try docker with a simple webapp : docker run -d -v $(pwd):/app -p 8080:80 image_name I have docker listen on 8080: tcp6 0 0 :::8080 :::* LISTEN ...
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1answer
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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: ...
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Network Vulnerability Scanner placement on network

We have implemented/are implementing a network vulnerability scanning process, and we have chosen to use Qualysguard. Qualys supply a scanner appliance for the internal network scanning, which ...
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what is a good public available iptables script for ddos mitigation?

what is a good public available iptables script for ddos mitigation?
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2answers
1k views

Cisco ASA Security Contexts: Any Real World Installs?

We are looking at deploying a Cisco ASA 5520-I am looking at the security contexts feature, and was wondering if anyone has deployed their ASA in this way, and how it is working out for them. Have ...
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2answers
341 views

What criteria do you use for evaluating Client-Side / Endpoint security products?

What features are important to you in client-side AV and Firewall products? Who benefits from these features? Managment, the end user, helpdesk. Are there features that are being 'sold' by the ...
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2k views

Effectively limiting outgoing firewall traffic to frequently-changing IPs

PCI DSS 1.2.1 states: Restrict inbound and outbound traffic to that which is necessary for the cardholder data environment. Verify that all other inbound and outbound traffic is ...
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1k views

Firewall rules to block unwanted protocols on given ports

Does somebody has an idea, that what kind of iptables/pf rule must i use to achieve this?: i only want to allow these connections [on the output chain]: on port 53 output only allow udp - dns on ...
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1answer
193 views

Firewalk through a Firewall on our subnet

Having trouble firewalking. I am trying to determine all the open ports on my firewall/gateway. Here is my lab network diagram: (Skip to the bottom of the following explanation for a direct list of ...
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1answer
162 views

DMZ Firewall settings

I am involved in project where I have to install a new server for a new application to a preexisting production network. The new server shall sit in the DMZ and two controllers will sit on the ...
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1answer
64 views

Is there such thing as an OS “internal firewall”

I was wondering if there is such thing as an OS "internal firewall". If it exists, it must be under a different name. I am looking for a way to control which applications can talk to which other ...
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1answer
92 views

Can NATs and firewalls blacklist IPs when trying to UDP hole punch?

I am developing a P2P application that will make use of UDP hole punch to connect two peers behind NAT. When dealing with connections between a cone and a symmetric, unpredictable NATs, however, hole ...
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3answers
7k views

Securing a network attached storage on the internet

I recently purchased a network attached storage for personal file storage and would like my family members to store files on the device from their computers as a remote backup. I'd like to secure ...
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1answer
211 views

firewall with cloud based malware analysis risks

Palo Alto, and probably others firewalls will offer it, has a feature to do malware analysis in a separate (cloud-based) process that does not impact stream processing. What I would like which risks ...
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477 views

What problems if any are caused by opening a port in the firewall that no program listens on?

I have a port forwarded and open in the firewall that I sometimes use to play games with friends over the internet. The game server doesn't run 24/7, only when I'm actually playing is something ...
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How can attackers bypass firewalls? [closed]

I have read the Wikipedia article on firewalls but don't understand firewall security and how an attacker from the outside can bypass the firewall to hack target system. We all know it happens but ...
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8answers
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How to block some websites in a small office?

I had a wireless connection in my office with one laptop. Now I bought two more laptops for my employees, and I give them Internet access. I want to block a few websites. My current connection is ...
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2answers
929 views

How does a firewall help to protect a server?

Since a potential attacker will exploit the services that are already open to public by firewall rules, how will a firewall help to protect my server from attackers?
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3answers
10k views

How to create ssh tunnel using netcat?

I want to create reverse connection between two machines, but these is a firewall in the middle preventing all connections, except ssh. I want to create ssh tunnel using netcat, could you please tell ...
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3answers
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is it worth to implement a firewall on a web server you control?

I see the main reasons for a firewall on a web server to be defense in depth and extra cushion for a possible admin error of running an unnecessary daemon. I'm trying to see if I am overlooking ...
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357 views

What does a switched network protect us from? What does it not protect us from?

There seems to be some misconceptions regarding what a switched network will protect us from, and what technologies/precautions a secure environment requires when segmenting trusted users from hostile ...
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How can reverse proxies be used to bypass acceptable use policies of a company?

I am wondering how reverse proxies can be used to bypass company acceptable use policies? What can be done to prevent it?
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2answers
1k views

Reverse shell connections

Why are reverse shell connections so popular in the event of a successful intrusion? Many "hacking" videos show this and it is often seen in practice. Would not most servers restrict outgoing ...
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208 views

Can firewalls get affected by the traffic they process

Does such attack exist? Forgive my wild imagination but is it possible for a hacker to pretend/try to communicate with a service on the server and when the firewall examines the traffic it get's ...
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1answer
115 views

Why guest's connections can pass host's firewall?

I've been wondering about this. Assume a host with a strong firewall setup (for example only allowing port 80). That host has some virtual machines without firewall. Why the connections made on ...
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If a port is closed how come you can still use it?

What does it actually mean for a port to be closed or stealthed? According to tests I've run all my ports (tested) are stealthed but clearly I can still use the internet. Also are the terms "blocked" ...
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127 views

Decrypt and then re-encrypt all requests to the internet at firewall level

I don't have strong skills about this matter but I am very curious about the following communication so may I ask: One institution sent a message to all network users saying that "all requests to the ...
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596 views

Using only a firewall, how do I protect a database server from be exposed?

If I had two firewalls, I could put a web server within a DMZ and then with the second firewall restrict the access to the DB server. However, If I only have one firewall, how could I accomplish ...
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SYN flooding attack causing high CPU on hardware firewall

I have a ZyWall USG 200 firewall. A few days ago there was a SYN flooding attack on it causing 100% CPU load. After investigating it turns out this was attack from a single IP address and while the ...
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2answers
224 views

How to red team against firewalled architecture?

Prior Knowledge I understand the types and differences between firewalls. I have (what I believe to be) a relatively good mental model of a firewall. I understand routing, iptables, signature ...
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why blocking incoming traffic does not block chatting or VOIP

I just recently blocked all incoming traffic(all local ports and all external ips) in my windows 7 firewall and I understand that will not stop me from accessing websites as browsing needs outbound ...
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290 views

Blocking executables at the firewall in the enterprise

The infrastructure team in our medium enterprise has requested blocking of all executables at the firewall. We have a firewall which is capable of DLP, so therefore this can be set up fairly easily. ...
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555 views

Servers: Why a separate device for a firewall, aside from reduction in IP spoofing or increase in performance

Why should the firewall be outside the server, excepting these two items Take the performance impact of noise off of the server. Add a physical layer between devices so they can be on separate ...
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2answers
206 views

Firewall egress filtering / quick whitelisting

Suppose your Aunt or Uncle is easily fooled by phishing attempts and their computer has multiple root kits and key loggers running. Assume their computing habits will never change. Looking at his ...
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390 views

Are local firewalls necessary

Is having local firewalls enabled on machines actually necessary if you run hardware based firewalls like pfsense or a netgear fvs338 and use that to control in/out bound connections? I personally do ...
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571 views

Configure Linux to allow network activity based on binary?

On Windows, rules can be added to the firewall to allow/deny network traffic based on which binary is sending/receiving the data. Can this be done on a Linux box, and if not, why not? Is it a bad ...