Concerned with software or hardware firewalls

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1answer
153 views

Using nmap to bypass a firewall and perform OS fingerprinting

How can I use nmap to perform operating system detection on a system which has all of its ports filtered by a firewall? Is there a way to bypass it? I have tried: syn scan, xmas scan, fragment scan,...
1
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1answer
52 views

Does a Web Application Firewall only protect OSI layer 7?

Does a Web Application Firewall (WAF) that is protecting application layer 7, as well protect other layers of the The Open Systems Interconnection (OSI) model?
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0answers
13 views

Firewall configuration [migrated]

ALL, I used to be a happy user of ZoneAlarm. However recently I needed to open a port on one of my machine (Windows 8.1, port 1433 for SQL Server) and I found out that this is apparently an ...
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0answers
9 views

Using both a firewall and vpn on android [migrated]

Is there a way to use both a firewall and a vpn app on android. I have tried allowing the vpn through the firewall but one invaraibly goes off when I start the other. Is there some way around this -- ...
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3answers
560 views

Security risk with using internal IP on public DNS

A web server inside the office network which is accessed by staff internally and the internal DNS resolves web.company.com to the server's LAN IP. Publicly, company.com nameservers belong to their ...
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3answers
15k views

Port Scan Detected and Blocked! - Bitdefender 2014

I have Bitdefender Total Security 2014 Recently I have been getting the message/alert "Port scan detected and blocked", I did not cared about it much till I getting increasing specially in a specific ...
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2answers
158 views

Acceptable secure solution to replace static IP addresses for a web application

I am currently working as a technical lead on a project at a financial institution and have a question about how to provide the same level of security expected by the business in an application we are ...
4
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2answers
4k views

Windows Firewall Connection Security with Certificate

I've been fiddling with the Windows firewall configuration of some computers within a VMWare based LAN (no domain). To aid in my testing and debugging, I created a small, self-hosted console ...
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0answers
48 views

How to view which ports are opened on firewall?

I have a perimeter modem that should have a firewall, but the admin portal does not display much useful info on what settings it has and whether it is on or not. How would you get a list of open ...
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1answer
37 views

Security Best Practices - firewall Outgoing traffic vs incoming [closed]

For a PC that only needs basic internet access, for web browsers and updates, generally speaking, is there any need for incoming ports to be opened on the pc's firewall? If outgoing port filtering is ...
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2answers
7k views

How secure is blocking all incoming connections on my ADSL or cable router?

My router, an up-to-date ADSL Fritz!Box 7340 router with a fixed leased IP address, has been configured to block all incoming traffic. Assuming, for the sake of argument, no extra security is ...
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10answers
52k views

Why do people tell me not to use VLANs for security?

I have a network, where a have a couple of VLANS. There is a firewall between the 2 VLANs. I am using HP Procurve switches and have made sure that switch-to-switch links accept tagged frames only and ...
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3answers
57 views

How to pass website firewall, in PHP? [closed]

Recently, I have posted a question, (http://stackoverflow.com/questions/37494896/how-to-save-file-from-url-to-web-server-by-php). And, there is an answer in question. In this answer, he said: "So the ...
2
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2answers
79 views

Dedicated OS vs Debian for SOHO Firewall? [closed]

I want to set up a firewall for a small office. I have a server on which I can install an OS of my choice. I was thinking of trying pfSense but ran into some testing problems and tried IPFIre (Linux ...
0
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1answer
40 views

Network configuration: Preventing my computer being used as a proxy?

I recently installed an extension for Chrome called Hola (skip to next paragraph if you know it). It calls itself a VPN, but is basically a proxy pool AFAIK. You can choose a country from a list in a ...
12
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3answers
13k views

Proxy vs. Firewall

I understand that very simply put a proxy is a sort of 'man in the middle' allowing/denying access to certain services/resources. Strictly in terms of security (I mean here privacy, parental control ...
2
votes
3answers
991 views

iptables: plaintext password protection

I'd like to find a way to block or restrict my access to the web-pages where my password is sent as a plaintext on the internet. Let's assume if I have the same password for all web-pages, is it ...
1
vote
1answer
440 views

What's a secure firewall rules using UFW?

On my Ubuntu server I have these services running: netstat -tlnp Active Internet connections (only servers) Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program ...
26
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3answers
5k 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
16 views

Does altering the routing table to my hub defeat the purpose of a VPN?

I am running a VPN on my server with openvpn. When running openvpn I have a shell script that runs afterwards: ip rule add from 192.168.0.19 table 128 ip route add table 128 to 192.168.0.0/24 dev ...
3
votes
1answer
64 views

How does firewall differentiate between browsing and downloading?

The firewall installed at my college's router allows me to surf the internet but never allows me to download any package that has a size more than 100mb. I wonder how exactly does it differentiate ...
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3answers
13k views

How to protect myself against paid DDoS services?

I am domestic user and I am getting attacked regularly by a guy that hates me. Here is the background story: that guy uses Skype resolvers (tools offered by paid DDoS services) to find out my IP ...
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1answer
79 views

Multiple instances of programs allowed in Windows Firewall

I am new to Windows Firewall. While allowing a program through Windows Firewall, I found multiple entries present for Firefox and Java. Why is that?
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1answer
41 views

Packet Filter with Access Control List

http://i66.tinypic.com/29p50zp.png Can anyone explain how to read and understand row 1,2 and 3? My understanding for row 1 is : If any inside packets want to go to outside via any source port to ...
3
votes
2answers
256 views

Is it safe to not update Windows if you dont accept any incoming connections?

I see this guy shared his thought: How to be safe even without most updated Windows updates So he claims that as long as you do not accept any incoming connections and just use sandbox of Chrome, ...
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0answers
26 views

Cisco ASA Access List Summary / Visualisation Tool

I have a Cisco ASA firewall config with about 50 interfaces and approximately 4000 rules. I am trying to find a tool that can sort this into an easier to consume list or even a visualisation of the ...
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3answers
641 views

Suspicious VMware connections that bypass firewall

I'm running VMware 5 and I have found that when I start up VMware I see two connections: TCP 10.100.100.161:55555->as-40816.engx.vmware.com:https (ESTABLISHED) TCP 10.100.100.161:55556->a184-85-...
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votes
1answer
56 views

How does PeerBlock generate range descriptions?

How does PeerBlock generate the range that it displays? I thought it was through some DNS lookup, but when I do the lookup I get LeaseWeb Content Delivery Network for the attached screenshot. Instead ...
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2answers
147 views

Why can't home internet users communicate with their peers? [closed]

As a home internet user, why does my ISP block my communication with any other client on the same subnet as mine? It is done for security obviously, but what is the risk? Update: as clarified by ...
3
votes
2answers
75 views

Why does our network firewall drop netbios-ns packets?

In our local domain environment, we use Sophos UTM to protect our network. When I check the firewall logs, I can see that a huge number of packets dropped by the firewall are netbios-ns (UDP 137) ...
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2answers
2k views

Is it Feasible to Block Connections That Windows 10 Uses to Push/Pull? - ie: Phone Home, Watchers, Monitors, Onedrive, Cortana, Bing, Shadyness, Etc?

Even with all the privacy, sync, and p2p settings off, using an offline account, I don't feel safe using Windows 10 for a business. I would like to restrict its ability to communicate to Microsoft (or ...
6
votes
3answers
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 ...
7
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3answers
38k 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 ...
4
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1answer
310 views

Can a Cisco ASA 5505 block this DDoS attack?

Since more than a week ago, my dedicated server (located at ovh.com) has been under TCP SYN (I think) attack. OVH don't care about it but this attack is killing my server with a high CPU load (...
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2answers
98 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
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1answer
107 views

Raspberry Pi IDS/FireWall - Should I? [closed]

I was excited to setup an IDS/FireWall with my new Raspberry Pi on a standard home network. Reading threats to SSH and Linux, now I am not so sure. Setup by an experienced amateur I'm now concerned ...
6
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1answer
123 views

Would a DMZ be safe to use with a software firewall for home networking?

If I set up a Windows 10 PC with a software firewall (TinyWall, which is a front end for Windows Firewall) and blocked all traffic except for a few applications and ports I would be using (Minecraft ...
1
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1answer
48 views

Firewalled bots in UDP p2p botnets?

One thing that I don't understand about peer to peer botnets, is how a bot stays connected to the network considering the protocol used is UDP. Since the UDP is connectionless, and the bot is behind ...
2
votes
2answers
143 views

How can the nmap tool be used to evade a firewall/IDS?

Some techniques are used to secure the operating system against network attacks e.g.: firewalls, antivirus software, an IDS like SNORT, etc. To take advantage of the nmap tool, is it possible to ...
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1answer
73 views

Can firewalls decrypt SSL packets?

I was wondering if the firewall has the ability to decrypt the SSL traffic. If so, the network admin is able to read the data in clear text at transit.
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0answers
40 views

DDoS Solution for request floods [duplicate]

What are the mitigations to protect from ddos? Is using firewall like cloudflare would help or not? My use case is just want to make sure that no one is sending flood of requests i.e. thousands per ...
1
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1answer
92 views

UDP DNS & Firewall

This question might be simple but please understand my lack of knowledge. I am seeing a lot of DNS packets dropped by our firewall (sophos SG125) by default rule 60001. There are three Domain ...
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0answers
90 views

Modifying shell code to bypass Windows Firewall

As part of my OSCP's training, I'm supposed to get a shell on a Win7 machine using browser's exploit (MS12-037) with Windows firewall on. I have an idea but I'm having hard time applying it. What I'...
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2answers
89 views

Determining Firewall settings (Ports, etc) for specific applications

How can we identify the network or network firewall requirements for a Desktop or Web application. Meaning what ports are required by the applications. How the Cloud and non Cloud networks communicate ...
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2answers
55 views

Is there a difference in security between an IP address white list and a domain white list with TLS?

It seems to me that an IP address white list relies on easily spoofed information, while a domain white list, if it forces TLS, at least, relies on the validity of the certificate systems. I may be ...
1
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1answer
82 views

How does a malicious user connect to a private network?

I have followed these instructions for setting up a couple of servers to have private networking. It ends by saying "It is important to secure your private networking interface the same way you would ...
2
votes
1answer
166 views

Antivirus monitoring activity: why do they not have an internal firewall to prevent processes' access to user's documents?

A question that arises after an updated and licensed version of Norton Internet Security has detected a trojan installed in my new laptop (Windows 7 installed on 26 Aug'15 and fully updated). Trojan ...
2
votes
2answers
132 views

How to block I2P and Freenet to my network?

I am trying to find a way to block I2P and Freenet darknets in a corporate network. Does anyone know a way to block them (on firewall)? Do I need to close particular ports or block entry nodes (like ...