Concerned with software or hardware firewalls

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2answers
555 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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2answers
923 views

Can a firewall tamper with email attachments?

I am using Thunderbird as an email client for managing my different email accounts. Yesterday my friend sent me an email with a PDF attachment. Today when I tried to open the attachment I get the ...
4
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1answer
447 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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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 ...
4
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2answers
544 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 ...
4
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1answer
366 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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3answers
8k 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
287 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
49 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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2answers
2k 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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2answers
1k views

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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4answers
2k views

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
334 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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1answer
947 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 ...
4
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1answer
90 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 ...
4
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2answers
180 views

Long character sequence in first string of HTTP GET request breaks the web service's HTTP response. Buffer overflow?

During my current security audit test I've stumbled on something I can't possibly comprehend. The behavior exhibits signs of a buffer overflow in the target or in some intermidiate service (HTTP ...
4
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1answer
144 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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3answers
6k 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 ...
4
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1answer
210 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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4answers
292 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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8answers
39k views

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 ...
3
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2answers
612 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
9k 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
3k views

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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4answers
338 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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3answers
2k views

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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1answer
114 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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4answers
2k views

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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2answers
4k views

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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3answers
3k views

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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2answers
108 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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3answers
199 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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2answers
538 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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5answers
3k views

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 ...
3
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2answers
218 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 ...
3
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2answers
257 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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3answers
524 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
134 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 ...
3
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3answers
365 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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3answers
2k views

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 ...
3
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2answers
514 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 ...
3
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2answers
8k views

Disabling windows firewall remotely

i use metasploit for pentesting windows 2003 sp2 server but when windows firewall is on i am not able to perform pentest successfully is there any way to disable firewall remotly?
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2answers
95 views

Why does a nmap scan give different results depending on whether it's run from inside or outside a LAN

I am testing/setting up a Thompson TG585v7 router/firewall. Results when running nmap from a computer INSIDE the LAN $ sudo nmap -O 210.86.xxx.xxx Starting Nmap 6.40 ( http://nmap.org ) at ...
3
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3answers
6k views

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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1answer
253 views

Blacklisting during a penetration test?

So i had a debate recently where one of my colleagues believed that by launching a penetration test (one requested by our clients) from our one of our IP's we could potentially get that IP/all IP's in ...
3
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2answers
2k views

How secure is opening an incoming port for a java application?

If a java application is listening on UDP port xxxxx and a firewall is allowing connections to that java application through the same UDP port xxxxx, what vulnerabilities will a Windows 7 machine be ...
3
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1answer
947 views

I'm using a Cisco ASA as a VPN endpoint. Where do the VPN clients get firewalled?

(Is this too application specific? It seems like a reasonable question that would be useful to other people...) So, I've got this ASA in front of a network that I didn't set up. It's been ...
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2answers
118 views

If nmap reports a port is open, does that ALSO mean a service is listening on the port?

I have a Thompson TG585v7 router/firewall whose firewall is configured to FORWARD several ports to a computer X54 within the LAN. These ports are in the range 1024 through to 2500 That X54 ...