Network Security - securing network infrastructure and connections

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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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2answers
257 views

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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2answers
489 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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4answers
1k views

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 ...
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4answers
1k views

Verify Mac firmware is not hacked…how to do?

I have a late model Mac computer. I allowed someone to plug in a USB drive, and my network activity changed afterwards. Normally, Little Snitch will report every app that uses the internet. Every ...
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3answers
312 views

What tools are available for distributing and syncing firewall rule-sets to multiple devices?

I am looking for a solution to be able to distribute and sync firewall rule-sets to multiple devices. There are a few solutions out there such as Playbook by Matasano but it comes with an expensive ...
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1answer
1k views

AWS VPC - should connections between instances be over SSL?

Say I have a few EC2 instances in an AWS VPC network, each assigned its own private address for the subnet at creation. Say one of them is a DB, and another one some kind of web app talking to the DB. ...
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3answers
2k views

Alternative approaches to using DMZ for securing communication to and from external web server outside firewall

I am a software developer with little network security knowledge and almost no knowledge of the current network architecture for the environment I work in. If I had any, I still would not want to ...
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1k views

How do I identify an unknown port/protocol that my IDS picks up?

Googling a port and protocol leads to a terse description at best, and a linkfarm in the average case. Most protocols on assorted, unknown high ports contain little or no plaintext, and often if the ...
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Private Tor networks: what are the benefits, and how would it be accomplished?

What are the benefits of someone building a private Tor network? ...One that is disconnected from the well-known network being used on the Internet at-large. My intent is to make Tor more ...
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1answer
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Security Operation Center (SOC)

I am looking for resources and details on establishing a security operation center (SoC) or network operation center (NoC) based on ITIL or any other applicable regulations. Where can I find good ...
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4answers
19k views

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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1answer
197 views

Trace large volume of web traffic, stopped at VPN

I have a web server. I recently received a large volume of web traffics, after tracking it down, it is coming over a commercial VPN provider. Is there any way to keep the tracing going, beyond the ...
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491 views

Popularity of Anomaly based IDSes

I've been reading quite some time about anomaly/behavior based IDSes for Web servers. I understand the downsides: possible high false positives, learning phase, constant training. My question is how ...
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2answers
691 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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4answers
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Has my network/computer been breached?

I'm not sure if this is the right site to ask, so I apologise if it isn't, but here goes. A while ago I started noticing some odd behaviour. My Gmail account was compromised, it seemed, and I had to ...
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2answers
818 views

SSH Tunnelling: How can I stop users being able to access services bound to localhost via port forwarding?

I want to be able to offer ssh accounts on my linux server for people to be able to use for SSH tunnelling. All accounts will be locked down with no interactive shell, for tunnelling / port forwarding ...
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3answers
4k views

Can I block the true IP address using X-Forwarded-For header in IIS?

All the traffic gets to my IIS server through a proxy. I can't block or white list IP addresses because all the traffic comes from the proxy's IP address. Can I use the X-Forwarded-For header with ...
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1answer
1k views

Deploying a campus WiFi network that authenticates against an AD LDAP

We are looking to deploy about 15-20 Cisco 1131ag access points on campus. I have been reading up on different authentication methods, but I don’t know what will be the best long term solution that ...
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1answer
4k views

Obtain credentials by spoofing WPA/WPA2 Enterprise network?

I have a large scale wireless network secured using WPA/WPA2 Enterprise authentication. Recently, I was made aware of the possibility that someone may use a dd-wrt router and a computer to spoof the ...
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1answer
867 views

How to get hold of and use WPA session keys?

I'm testing sniffing and decrypting my WPA2 wifi network traffic. But when using airdecap to decrypt the capture file (created by airodump) using my WPA passphrase I only get broadcast traffic. If I ...
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1answer
1k views

DSL Modem Compromised?

Just found out that the primary & secondary DNS servers have been changed to 95.211.156.101 & 5.45.75.11. I had the following setup in place. MAC filtering and WPA2 for WiFi. ...
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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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3answers
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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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708 views

LTE networks and MITM

2G would leave you vulnerable to spoofed base stations. 3G tried to somewhat fix that using mutual authentication. Now, I tried to check how LTE handles this but I couldn’t find any usefull ...
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220 views

Are temporary blocks sufficient response to network probes?

We have the option of using an automatic blocking feature of our firewall to temporarily block the source IPs of network probes. It is fast and automatic, and it expires after a set amount of time. ...
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1answer
932 views

I can receive all PADI packets for PPPoE connections of my ISP, is that a problem?

for debugging why my router wasn't connecting to pppoe i've tried to connect via the pc, it worked, then i started wireshark just to see what was going on, and i've seen that i can read all the PADI ...
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4answers
965 views

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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4answers
367 views

Worst case scenario of having the ability to remotely write files to disk as admin

I'm working on creating a program ("My Program") that will communicate with another program ("Their Program") via XML commands over a raw TCP/IP connection. Their program allows files to be written to ...
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5answers
5k views

What kind of attacks against home router's NAT do exist?

I always thought NAT was some kind of a security feature and I still think it is, because if it didn't existed the internet, respectively the clients behind NATs, would be even more insecure, since ...
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2answers
2k views

Is Access Control Through MAC ADDRESS a practical/secure solution

I run a small local gaming website with a custom admin panel I coded to let trusted members do administrative tasks through the software's API. Since their IP Address is dynamic, can I authenticate ...
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4answers
6k views

Is the US military secret network SIPRNet physically or cryptographicaly separated/secured?

I've read the Wikipedia articles on SIPRNet and NIPRNet (which are pretty light on details) and they are supposed to be considered separate. At the network level, are they technologically ...
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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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5answers
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Firewall demo - iptables

I have to make a demonstration about firewalls in my class as a student(university). It should be implemented using iptables on Linux. I am reading all the theories around them but I can't figure out ...
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4answers
532 views

“There's a firewall on the router into the building so you can turn the one on your computer off”

I know some people that, in regards to network security, argue that because the firewall on the router into the building is on, that makes the network secure and therefore, the firewall on Windows ...
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4answers
2k views

Is this type of ARP poisoning attack possible?

I am wondering if it is possible to paralyze a network by sending out a bunch of fake ARP response packets. Some basis: I recently read a moderately detailed description of how ARP and ARP poisoning ...
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3answers
19k views

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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4k views

Scanning my network with NMAP

Each computer is assigned one ip address on my network, and my ISP supplies one IP for my network. If I try to scan the ip supplied by my ISP what I got is the OS running on the router, running on the ...
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4answers
1k views

How can a company reduce exposure to packet spoofing? What solution should exist, but doesn't?

I'd like to understand what anti-packet-spoofing technology exists (or should exist) to verify an inbound packet. Maybe this is as simple as a Cisco ACL, Firewall Rule, implemented at the network ...
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3answers
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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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2answers
602 views

How to be safe from wifikill!

I recently found that my friend is using wifikill apk on his rooted android and I would like to get rid of that software as I always get kicked from my wifi. I have to give him the password of my wifi ...
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2answers
3k views

What is the difference between SSH and IPsec?

There seems to be similar encryption going into both. They both use asymmetric (RSA, elliptic curves, etc) for the initial key exchange, then go to some symmetric (AES, Blowfish, etc) protocol. I'm ...
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2answers
580 views

Suspicious 'upstream' traffic

We are seeing unusual amounts of traffic heading upstream on our WAN connection, during the day our system can exceed (or attempt to exceed) the 1Mbps limit imposed on the connection. I have PRTG ...
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8answers
2k views

Should I block visitors who seem to be probing my site?

I have detected some attempts to probe the security of my site. Should I blacklist their IP address? What are the considerations or tradeoffs to use in deciding when to block their IP address and ...
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3answers
3k views

Advantages of separating Web server from Database

What are the security advantages of installing the database of a web application on a server other than the one containing the web server?
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3answers
8k views

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 ...
6
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1answer
207 views

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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Snort Sensor Placement

I have a snort sensor monitoring some of my network being fed from a mirrored port. This mirrored session only monitors traffic between the firewall and peering switch. Since this just sees traffic ...
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2answers
5k views

Is opening port 3389 on a router and forwarding this to a Windows SBS 2003 server secure?

I know of a company who has port 3389 open on their router and forwards this to a Windows SBS 2003 server. The server has the Windows firewall switched on, is patched and has an up to date antivirus ...
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2answers
12k views

Detecting the presence of wifi devices

Is it possible, with a normal wifi adapter, to detect present wifi devices in the surrounding? Let's say, is it possible to detect an Iphone with wifi switched on in the range of my wifi adapter? ...