Network Security - securing network infrastructure and connections

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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
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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 ...
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4answers
723 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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487 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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1answer
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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 ...
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464 views

How to secure a modem/ wifi router without login?

A friend of mine has a DSL-modem/wifi-router from his ISP. The configuration page of the modem requires no login and no login can be set. It is said that there also exists a superuser but this is only ...
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506 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 ...
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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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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 ...
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Securing remotely accessible IP cameras that do not support HTTPS

I have some IP cameras set up on my home network, which is WPA2 protected. These cameras are setup to be accessible from the Internet thru my router's DDNS address, and port number. So for example, ...
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243 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 ...
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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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How do the root servers get updated with my name server? Is WhoIS information always in sync with the root?

I've never understood what happens behind the scenes when I go to my registrar and enter in my name server's information. Can someone elaborate on what happens when an update is made, and how it is ...
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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 ...
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4answers
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Pros/cons of using a private DNS vs. a public DNS

I was wondering why a company should use a private DNS. In comparison with a public DNS, which advantages does a private one have, and which issues can a public DNS create for a company? I'm new at ...
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304 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 ...
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1answer
465 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 ...
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1answer
830 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 ...
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317 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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767 views

Does DNSSec have any benefit if used with IPSec-enabled IPv6?

I'm not sure if the RFC's support a IPSec-only implementation of DNS, but if it does, what does that mean for DNSSec? Is DNSSec an IPv4-only technology?
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How to create your own RBL DNS Blacklist to prevent spam

I am getting sick of reporting the same old chinese emails to Spamcop now and would like to make my own small RBL list that I can easily add blocks of IP's to. I have a spare PC and static IP address ...
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467 views

How to protect a Wifi network from Microsoft WiFi Sense

Microsoft is deploying a new feature, WiFi Sense, which provides users a way to easily share passwords to wireless networks with all of their contacts. This introduces a new security failure mode: a ...
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How bad is the leaking of Internal IP addresses through external DNS

If an external DNS server is leaking internal IP addresses are there any significant security threats associated with this information leakage? Apart from most the obvious - gaining an understanding ...
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Can ICMP Redirects still be used to redirect traffic in a LAN?

I tried just tried to migrate a MITM attack using hping3 with ICMP Redirects in my testlab. hping3 -I eth0 -C 5 -K 1 -a 192.168.2.1 --icmp-ipdst 192.168.2.15 --icmp-gw 192.168.2.100 --icmp-ipsrc ...
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Management Network Best Practices

I am looking at setting up a Management vlan, on which I will put all the Management interfaces for my various networkable devices (Firewall Mgmt Interfaces, Server RAC, WAP Mgmt Interfaces, etc). ...
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617 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 ...
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290 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 ...
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What is War Dialing?

The topic says it all - I encountered the term in a PDF given to me. So ... what does the term/phrase 'War Dialing' mean?
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Why would a switch be configured to Fail Open?

I can't understand why a switch would be configured to Fail Open? Surely an attacker could easily exploit this by MAC Flooding which will cause the switch to act like a hub and broadcast messages to ...
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322 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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4answers
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How to tell if you're being ARP poisoned?

I am having some issues at work and there is a new network admin in place. I think I am being monitored so decided to run ArpSpy X in two scenarios: Over WiFi bridge pluged into cisco router to took ...
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Prevent network users from creating an unauthorized outgoing VPN connection to avoid network policies

Is it possible to prevent network users from creating unauthorized outgoing VPN connections to avoid network policies? Edit- What is the best way to detect unauthorized outgoing VPN connections while ...
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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? ...
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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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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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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 --> ...
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TCP Sequence Prediction and it's prominence in modern systems/networks

I have a question regarding your experience of TCP Sequence Prediction that I am hoping someone could help with. I am aware of how TCP Sequence Prediction works and how the connection can be hijacked ...
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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 ...
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What makes the Blackberry device and network more secure?

One of Blackberry's strongest assets is the "network" that it uses. Can someone explain, or link to technical information that covers what this secure network is, and what it does better than the ...
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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 ...
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569 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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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 ...
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Detecting(and locating) rogue DHCP server on a local area network

How would we detect and locate a rogue DHCP server on our local area network?
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How to bypass Nmap blockage?

I rent a server, and my provider seems to be blocking nmap. Is there any other tools I could use to test my home network from the outside? Also, does blocking nmap on a network provide any security? ...
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Why do I need a firewall on my router?

I just bought a new router, and as usual the router manufacturer make a big deal out of the firewall. I have never understood why the firewall is needed, sure, stopping dos attacks (such as ...
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2answers
515 views

What features do you look for in an Enterprise Log Management solution?

This question is for IT Pros, and people who manage a company's infrastructure. Developers should see this related answer for tools geared for them. What are your requirements for such a Event Log ...
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Encrypting All Network Traffic

For a corporate network, is there a way to possibly encrypt all network traffic on the local network? I would like to ensure that there is nothing left for chance to be packet sniffed. Not even ...
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How serious is a local virus in terms of network security

My colleague got a notification on his machine of a possible virus (through the virus scanner that is installed by default on all machines). He called up the tech department, and they simply told him ...
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Parabolic Denial Of Service — Would it work?

Would this DoS attack be effective: Attacker determines target (10.0.0.1) Attacker sends ack packets to a buch of web servers with a src addr of 10.0.0.1 Servers reply to 10.0.0.1 with syn packets ...
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Why don't wifi managers remember mac addresses for hotspots to defeat the jasager attack?

So I just learned about the jasager attack, via the wifi pineapple and it struck me immediately that it wouldn't work at all if network managers (privately) associated MAC addresses with hotspots and ...