Network Security - securing network infrastructure and connections

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A firewall without any extra features [closed]

I have Kaspersky Internet Security (KIS) installed on my system. I always keep it disabled, yet using a few practices, I kept my system virus free for years: I disabled autorun using these tricks; I ...
8
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3answers
11k views

How can I keep a roommate from seeing my web activity?

I have a roommate who is a network security engineer and I think he hacked our home network and now knows what sites I am visiting and what I am doing online. Although he is not stealing anything I ...
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1answer
1k views

Does restricting the names of computers allowed to connect to a wifi network provide any security

In response to a statement elsewhere that MAC address filtering was essentially useless for protecting a wifi network because it was trivially by passable by network attack tools, I was asked if the ...
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5answers
1k views

What Man-made Physical Threat Could Pose Severe Danger to a Server Farm?

I am writing a novel in which a researcher attempts to work against a study he is a part of by purposely sabotaging operations on the research compound. I am wondering if the following is plausible. ...
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2answers
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Using RSA with 3DES instead of plain 3DES. Does it make sense?

I have a large legacy code. Currently it is using 3DES encryption for a network based application. It encrypts data packets with a main key. This key is used to encrypt and decrypt (symmetrical). And ...
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2answers
354 views

What is secure enough for web applications?

we intend to build a network in a small health center with No Internet Access it is expected to have 30 terminal machines, all machines will use an electronic medical record web application we want ...
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3answers
13k views

with IPv6 do we need to use NAT any more ?

I'm wondering how to use NAT with IPv6 ...seems that you don't even need it any more. So what exactly is the concept behind firewall configurations in IPv6 environments?
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2answers
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sniffing/recording GSM 3G signals

Is it possible to sniff or record and process GSM 3G signals (from some reciever) given that there is no other signals interrupting etc (the most comfortable conditions) Update (with some supporting ...
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4answers
7k views

How to detect hosts running in virtual machines with nmap?

I have to determine if a given subnet has virtual hosts. Are there any ideas about what switches to use?
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3answers
3k views

Encryption on mobile phone - myth?

Well, about six months ago I had pleasure to meet Harald Welte and when he talked about m-banking (banking via smartphones) he said that the most people thing it's safe while, in fact, mobile ...
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5answers
22k views

Multiple VPN clients in parallel

If I were to run more than one VPN clients on my machine, simultaneously, what risks would be involved? E.g. are there technical conflicts, such that it wouldn't work right? Could there be ...
8
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1answer
856 views

Is it possible to recognise and prevent MitM attacks on devices which use self-signed SSL certs?

I use both Linux and Windows at work on a large enterprise LAN. The majority of the network configuration is out of my reach. Certain SaaS applications that are hosted locally on the enterprise LAN, ...
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4answers
5k views

Block all BotNets and TOR addresses from accessing our site

I've heard that many DOS attacks and general "black hat hacking" attempts occur over the TOR network. Is it possible for me to dynamically block source IP's by their presence in a BotNet or similar ...
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6answers
2k views

How can I restrict access to network data by an unauthorized computer that connects via Ethernet?

I assume I can configure most routers to only assign IP addresses to specific MAC addresses, as is possible with wireless routers. However what if a computer is connected via Ethernet and does not ...
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3answers
3k views

Risk of configuring MySQL for remote access with a dynamic IP address?

I'm looking to make a MySQL database on a VPS, accessible to my home PC through cPanel. cPanel wants the domain name or IP address of the remote machine. However, with standard DSL, I have a dynamic ...
8
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4answers
652 views

CAM table attack in 2011?

Today's switches are vulnerable to CAM Table attack? https://secure.wikimedia.org/wikipedia/en/wiki/CAM_Table
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2answers
9k views

Recommended Cipher Suites for TLS 1.0, 1.1 and 1.2

There are a lot of cipher suites defined in the in the specifications itself of TLS 1.0, 1.1 and 1.2. And furthermore, there exist RFCs which add even more cipher suites to a specific version (e.g. ...
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3answers
430 views

Securing a LAN without Physical Security

I've got an interesting dilemma. I have a large (50+ users) office that is going to be on the campus of a local university. The purpose is to foster collaboration, etc, but the open environment is ...
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2answers
8k views

How can someone hack my PC if I am connecting to the internet through NAT?

If I own a private IP address, 192.168.2.1 for the sake of it, and I am physically connected to my router, which it's internal interface is 192.168.2.254 and it's external interface is some public IP ...
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1answer
12k views

Are open ports dangerous?

I have forwarded port 80 to WAMPServer and 25565 to the MineCraft-server running Bukkit. (http://www.bukkit.org/) Am I vulnerable to attacks. Can hackers attack me if WAMP-server is running or if it ...
8
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1answer
439 views

Is the system bios and network card protected by the OS firewall?

My question arises from trying to understand new types of spyware that target the system bios and/or network card. Is the system bios and ethernet card both protected by an OS firewall set to deny ...
8
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2answers
1k views

Spoofed IPv4 and IPv6 addresses over the internet

I have a few questions regarding IPv4 and IPv6 spoofing. Might as well just list them to be concise: What's the usual routing policy for ISPs' routers in regards to spoofed source addresses? i.e. if ...
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2answers
244 views

Retaining institutional knowledge of a complex infrastructure (checkpoint, juniper, etc)

In the next month my functions will be expanded to include IT security (firewalls, VPN, PKI) in a big complex infrastructure. Can I ask you for advice on how-to be well prepared for it? What sorts of ...
8
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1answer
231 views

Are multiple network interface still recommended in a virtualized world?

Before the virtualization era, it was recommended to have several network card on a physical server : 1 for production dedicated network (only application's stream like http, SQL*NET, ...) 1 for ...
8
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1answer
182 views

Deanonymizing users by introducing structured delays to the network?

Here is a scheme for deanonymizing a user that I've been thinking about, just out of curiosity. I tried searching for it but didn't find much. Does this technique have a name? Are there any papers or ...
8
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1answer
899 views

How secure is the apt-get install command against man in the middle attacks

I think the title says everything, how secure is it to use apt-get in a network with an attacker who injects his own packets and blocks the original packets (man in the middle).
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5answers
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Creating tunnel with most ports closed?

How can I create a proxy tunnel from a network that has all ports but port 80 closed? I guess I'd have to bind SSH on my server to port 80, but would that introduce problems to my home network since ...
8
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1answer
285 views

What is the security vunerability in this scenario?

I saw this question: Suppose a university with address block 12.1.0.0/16 has a link connected to AT&T, where the AT&T router forwards packets destined to 12.1.0.0/16 to the university ...
8
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1answer
396 views

Is Chinese great firewall white or black list based? [closed]

Is a new website blocked by default in China ? I just put online a new website dedicated to chinese people (a working days calculator in China, nothing subversive indeed). However a friend of a ...
8
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1answer
736 views

What are the main issues and best practice security controls when exposing SIP and H.323 to the Internet?

What are the main issues and recommended controls when exposing SIP and H.323 to the Internet (could be for voice, video, and instant messaging traffic or all three)? Specifically I'm looking for ...
8
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2answers
294 views

Can you tell if an attack is successful by looking at IPS logs?

In my organization, we have an IPS behind a firewall. Each time a security event is triggered, I am left to wonder if the attack is really successful. For events that are set to drop in inline, we can ...
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2answers
522 views

How do you Secure VOIP in a large organization

As part of a large organization looking to implement VoIP, to get on the bandwagon of savings and converged network focus, I'm being asked to look at the security concerns to develop a policy to help ...
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3answers
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Secure PXE network OS installation

How can one make sure that when PXE is being used to boot a remote operating system, that the data being sent is encrypted (or at the very least that integrity is maintained)? Would it be possible to ...
8
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3answers
190 views

What are the risks to a network if a single computer is compromised?

If I open up a dedicated server on my home network to accept incoming connections (HTTP, SSH, etc) and that machine is compromised by an outside attacker, what are the risks to other devices on the ...
8
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1answer
570 views

SSH Brute Force Dictionaries

Request for logs please. So, I had an interesting question posed to me around geographical trends in SSH brute force attempts. The question being "has anybody ever looked into the prevalent SSH ...
8
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1answer
259 views

Using / finding covert channels in inter-process communication

I've got a class exercise that involves a virtual game of Werewolves/Mafia. We're not really taught how to do anything in this class, which makes it hard for everyone to do the labs. The idea is that ...
7
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6answers
299 views

Why shouldn't I run other applications on a Firewall?

If I want to use Ubuntu 11.04 as a Firewall in SOHO environment, then I just can't figure out what is the bad thing about installing GUI on it (e.g.: XFCE)? The only opened port to the world (wan ...
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8answers
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How to block some websites and torrent usage in a small office?

In my office there are approaximately 25 systems are connected through network and all having internet accessibility.but some people are missusing this facilities like downloading films from torrent ...
7
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2answers
3k views

Dictionary Attack on Wifi

I know a few people with pretty weak passwords. What kind of systems exist to prevent dictionary attacks? Would it make sense to restrict the number of connection attempts in a certain timeframe? ...
7
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4answers
685 views

Is Stonesoft's “advanced evasion technique” a major problem?

A month ago, Stonesoft (an IDS constructor from Finland) has launched an alert about Advanced Evasion Techniques. With these techniques, they claim to be capable of launching attacks on a network ...
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10answers
634 views

networking and security

I'm trying to pick up networking security within a reasonable amount of time. I'm not specifically looking to learn about all the little tools that are available (although I do want to know about ...
7
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4answers
759 views

IP Address spoofing?

According to: https://secure.wikimedia.org/wikipedia/en/wiki/IP_address_spoofing "this technique is mainly used when the attacker does not care about the response or the attacker has some way of ...
7
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4answers
3k views

Security Services on Edge Router vs. Standard Firewall

If I can run a site to site VPN, NAT & Reflexive ACLs on a edge router (plus normal routing functions), what would be the use of running a stock firewall behind it? For instance, Core Switch --> ...
7
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2answers
298 views

What to add to a repeating security checklist?

I work in a smallish company (100-200 computers and a handful of servers) and I am trying to come up with a checklist of things to check at a regular basis, such as weekly, monthly, etc. We use ...
7
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2answers
2k views

IIS IP Address Restriction - can I rely on it online?

I've been told that I might have more luck posting here than on Stack Exchange, so here goes: I'm looking for a way to lock down a 3rd party application in IIS. It's a web service, so there's no ...
7
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2answers
512 views

What does a Firewall mean by “connect to TCP port without your permission”?

McAfee is reporting incoming network connections blocked from IPs like 198.252.206.149 (StackExchange Inc.), 54.179.231.116 (Amazon Technologies Inc.), 74.125.68.106 (Google Inc.), etc. The ports ...
7
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1answer
506 views

different portscan tools give different results

I have different results as of my open TCP ports. When using nmap -sS 127.0.0.1, I get some 5 usual open ports, but when using osx built-in tool as stroke, I get those 5 ports plus 5 extra ports. How ...
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6answers
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How to detect eavesdropping by your ISP

I've noticed some funny behavior lately with my home Internet connection such as connections dropping frequently, rate limiting occuring, and packet loss. I know how to get around this online, use a ...
7
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3answers
727 views

Is IPv6 with NAT less secure than IPv4?

This is a follow up to a snippet from another answer. There, user Ninefingers writes: (...) only allow outbound connections, ever. Do this in spite of NAT as IPv6 will make those NAT defences ...
7
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2answers
1k views

Any advantage to securing WiFi with a PSK, other than to keep out unauthorized

As I understand WiFi with a PSK, such as WPA(2)-PSK or WEP, anyone on the same network can decrypt anyone elses packets because everybody has the same key. In which case, if you are not going to ...