Network Security - securing network infrastructure and connections

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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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3answers
7k 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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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 ...
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8answers
1k 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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4answers
3k 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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2answers
428 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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1answer
185 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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3answers
2k 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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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
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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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2answers
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Initial steps of network mapping

In light of recent security breaches hitting the news, it's been all hands on deck at my work as far as security. I'm trying to pen test our network. I have a very basic question. My Question You ...
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1answer
160 views

Wireless auto-join on laptops

Maybe I have the wrong idea but this is a question that has been floating in my head for some time. Whenever you use an iPhone (or a Mac, Apple products seem to be more prone to this because it ...
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2answers
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Need help identifying the OSX process that's generating strange network traffic

Since the past few days, I noticed that my router was a bit slow, and was restarting by itself at times. When looked at it's logs, they had entries like: Friday Jul 13 13:09:02 2012 1 Blocked by DoS ...
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3answers
854 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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2answers
599 views

What risks does WPA carry?

A family member of mine would like to be able to play old PSP games online. Unfortunately the device does not support WPA2, and my network is strictly WPA2 AES secured. What are the risks involved in ...
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1answer
281 views

What are the security measures taken on GPS transmissions?

I was just reading this article on how phone GPS work and the improvements that Apple had done to reduce the amount of time those calculations take on a regular iPhone. That makes me wonder: what ...
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1answer
4k views

High concentration of UDP traffic, good or bad?

Should a network have a high concentration of UDP traffic compared to TCP traffic bad for a network especially in the context of network security? I'm looking at my organization's network protocol ...
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2answers
6k views

Is it possible to speed up WPA/WPA2-PSK cracking using a rogue AP?

We know that WPA/WPA2-PSK uses a PTK (Pairwise Transient Key) for each client to encrypt the communication. This PTK is generated through the process known as 4-way handshake. As told in the related ...
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2answers
952 views

What are the security risks of the Service Bus, and how do you mitigate them?

The Service Bus is software that can be installed on Windows or rented on Azure and allows someone to relay SOAP/WCF information over the internet in the form of a XML over HTTPS payload. One risk ...
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1answer
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Using skype for an attack

I am curious about something; let's say someone randomly added me to Skype and tried to initiate a chat with me and I want to know more about them but I am worried if they can do some damage. My ...
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3answers
697 views

Does NAT break source port randomization?

The standard defense against the Kaminsky attack is to use source port randomization for all DNS requests. Does NAT break the security benefits of source port randomization? In more detail, consider ...
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2answers
10k views

Is NAT Loopback on my router a security problem?

Some DSL routers prevent NAT loopback. Security is sometimes cited as the reason. Is NAT loopback really a security issue? And if so, how is this exploited? NAT loopback... where a machine on the LAN ...
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2answers
244 views

What implications does IPv6 have for internet worms and script kiddies?

Though IPv6 is not here yet it one day we will all lose our familiar IPv4 addresses and be communicating over the internet solely with IPv6 addresses. What interests me is the implications this has ...
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2answers
332 views

Design proposals for enhanced security for parts of Internet, e.g. for banking?

There is some recent discussion of some sort of "multilevel" internet, with e.g. a level defined for banking in which access is only granted after special authentication with "true names", special ...
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3answers
481 views

How can an IPS be fingerprinted?

I'm not trying to solve a current technical problem but I came across this and have been wondering how it's done. Intrusion Prevention Systems are supposed to let all network traffic pass through and ...
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4answers
12k 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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3answers
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Need a software that can monitor and log network traffic of installed applications [closed]

I need to monitor and log network activities of a specific software installed on my system. I know there are lots of network monitoring software out there, even system explorer has one built in. I ...
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1answer
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Exchange of DEK and KEK (encryption keys) between app server and key server

In my application, it is required to encrypt a user's data before inserting it into the mysql database. I am using AES algorithm to encrypt the data using a 256 bit hash (and is calling it Data ...
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4answers
9k views

Secure use of psexec or better alternative to it

I want to remotely start VMWare virtual machines (I own VMWare Workstation) and to this end I need to execute on host something like "vmrun -T ws H:\VMWare\VM1\VM1.vmx nogui" with user desktop ...
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1answer
353 views

Epson Projector security threats

I have an EPSON PROJECTOR (model EB-824H) And I would like to use it in our company. As I know (but not sure) this kind of projector has no WIFI,no network card and there is no HD in this PROJECTOR It ...
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2answers
3k views

Strange STP traffic in my network, possible MitM attack?

I live at a student dorm, where we are connected to a student network. The administrators of this network have forgotten to disable STP broadcast on non-infrastructure ports. Periodically, I lose my ...
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3answers
665 views

wlan security - why is it not possible to protect against deauthentication flooding

Wireless security (Wikipedia) describes security issues due to the fact that wi-fi deauthentication packets are unencrypted: Weak PSK passphrases can be broken using off-line dictionary attacks by ...
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159 views

Does a separate internet connection increase security for remote users?

Our network admin has requested that a single remote employee purchase a separate modem in their house for "work" traffic. I question if this is a legitimate security practice of any kind especially ...
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2answers
710 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
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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
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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
774 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
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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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4answers
777 views

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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1answer
3k 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
3k views

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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2answers
10k views

What is best practice for separation of trusted zones from a DMZ with a single firewall?

At our organization we have a single firewall sitting between our internal zones and the public internet. Currently all of our trusted zones are defined as different vlans on a layer 3 switch plugged ...
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2answers
186 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
811 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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5answers
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Is there a reason to disable root login, if SSH connections are restricted to a single IPv4 address?

I have a linux server running centos, and while hardending the SSH server, I asked myself: Is there a reason to disable root login, when only I (assuming my IP address is static, and i have direct ...
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4answers
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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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Resolving an IP address of a Remote machine to its MAC address

I wanted to know whether its possible to get the MAC address of remote node (computer/Access Point) if I know its IP address. I have heard that if someone sends you an email (even through gmail), you ...
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7answers
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What security risks exist in cell phone apps' data transfer?

Smartphones apps transfer various types of data over the provider's data network (or wifi, if enabled). What security risks are there in this transfer, and how can the risks be mitigated? I'm not ...
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4answers
172 views

software to keep a list of IP that try to access ssh over a set of rules and feasibility

i'm interested in software or set of scripts to keep a lists of filtered IP that attempt to brute-force ssh, and to label an IP as brute-forcing i would add some checks like: one attempt to log as ...
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4answers
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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 ...