Network Security - securing network infrastructure and connections

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What's the diff between blocking a port with a firewall and not starting a service on that port in the first place?

I was considering setting up a software firewall (pf) on my web server and did some research on them. Were I to do it, it'd involve basically blocking connections to all ports except 80, 443, and the ...
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2answers
11k views

How do Intrusion Detection Systems (IDS) work?

How do Intrusion Detection Systems (IDS) work? As I understand it, they monitor network traffic but what exactly do they look for? How can they tell apart regular activity from intrusions?
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3answers
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VPS security best practice

I've just signed up for a linux VPS to host a website I've been creating and I need some advice on the best approach to secure it. I've previously been hosting it off a VM in the house, but I want to ...
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1answer
807 views

Are there any security problems with Google false start for TLS?

Google recently announced false start in Chrome browsers which increased TLS performance by 30% http://news.softpedia.com/news/Google-Chrome-s-SSL-False-Start-201253.shtml I know TLS has been poked ...
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1answer
7k views

Is SOCKS secure?

In order to create a VPN, I open an SSH tunnel with a command like ssh -D 9000 user@host, and then I set my system's proxy settings to use SOCKS5 through localhost:9000. Well, setting up my home ...
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3answers
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How do I ensure data encryption on Samba transmission on *NIX systems?

I have a heterogeneous system (both MS and *nix) that communicates with CIFS/SMB. How can I ensure proper data encryption at the application layer?
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2answers
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Is IP spoofing relevant to TCP? Is it relevant for TLS or SSH?

I have read the TCP Connection Establishment on Wikipedia In brief the packets to start are SYN, with a (hopefully) random sequence number A from the client. SYN-ACK, responding, with A+1 and (...
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8answers
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Randomizing MAC addresses on bootup

Since it is possible to set custom MAC addresses, wouldn't it make sense to have a new one as often as possible/convenient (i.e. on bootup)? It would seem that is useful to both attacker and victim (...
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2answers
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Is this a secure data exchange scheme for a game?

I am writing a multiplayer game. I have a central server which processes everything. For data exchange I use HTTPS protocol. Because this is a game I cannot use computationally expensive systems like ...
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4answers
14k views

Security measures against packet sniffing

I work in a environment where packet sniffing can be easily done . I was worried about my confidential data . Please suggest how is it done and precaution which i can take at client level.
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3answers
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How can I detect if someone is sniffing network packets on the LAN?

I would like to know if there is a product or software that can detect if there is a sniffer currently on the network? In other words is it possible at all to detect if there is a network card on ...
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3answers
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Should a hostname ever be considered a secret?

I've been told in the past that you should never give out the host names of computers on your network. I can't think of any reason why this would be the case. Could someone tell me if they should be ...
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Egress filtering on an office network?

With an office network most companies will use ingress filtering to add a level of security, however few take advantage of egress filtering to protect their networks. The use of egress filtering will ...
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3answers
2k views

Is a predictable MAC address a risk?

If you knew from the public internet that a certain IP address belonged to a machine with a certain MAC address, can you see any security exposure associated with that? I know that some software will ...
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2answers
14k views

Is it possible to use the aircrack-ng tool to crack a WPA2 Enterprise network?

is this tool (aircrack-ng) capable of cracking into a WPA/WPA2 Enterprise network? This tool has major success cracking the passwords of WEP/WPA networks. If it can, how, but if not, is there another ...
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3answers
1k views

Are there valid reasons for spoofing an address?

This is a corollary to the question Why don't ISPs filter on source address to prevent spoofing?. Are there valid reasons to spoof an address?
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1answer
852 views

Kaspersky Antivirus “secure connection scan” as broken as Superfish?

I've read a lot about Superfish (and similar ad-ware) lately and I basically understand the vulnerability to MITM attacks. But I'm actually wondering if the "secure connection scan" by Kaspersky ...
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2answers
763 views

How does the Copyright Alert System work? Who has implemented it?

Some ISPs are participating in a Copyright Alert System that notifies content authors of violations of their copyright. I'm concerned how this oversight relates to my private traffic, and what laws ...
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1answer
2k views

What's are the advantages of L2TP/IPSEC over plain IPSEC?

As the title says, my firewall (Sonicwall) can do either IPSEC or L2TP/IPSEC for VPN connections. One advantage of L2TP/IPSEC I can see is that the client computer get allocated its own IP address on ...
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7answers
583 views

UNIX Servers: Possible intrusions or attacks that do not use any of the open listen sockets

What type of attacks are there that do not use open TCP or open UDP ports? Is it safe to assume that no open ports means no remote access? (Excluding the possibility that there is a badware already ...
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5answers
585 views

How can citizens prevent government-led Internet blackouts?

The United Nations now considers Internet access a basic human right. [PDF] Despite the questionable effectiveness of Internet blackouts in silencing a populace and preventing uprisings1, it's ...
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6answers
5k views

How can mini-computers (like Raspberry Pi) be applied to IT security?

It's no secret that thousands of $35 Raspberry Pi (Model B) computers have just shipped to people around the world. With these, and other similar types of computers becoming cheaper and more available,...
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4answers
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Is NTP vulnerable to DNS poisoning or spoofing attacks?

Scenario: Attacker somehow compromises the DNS lookup for the NTP server used by the victim (a web application) Victim sends DNS request for e.g. ntp.pool.org, which is responded to by attacker to ...
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5answers
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Can Skype chat be protected from snooping? Are there safe alternatives?

I use Skype a lot. With all of my clients, staff, contractors and friends, however, the acquisition by Microsoft worries me, as two of my clients are direct MS competitors, and I often work on long ...
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5answers
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Powerful security tools to use in penetration testing

I want to ask you about some good security tools you've used or heard about, please let us know the ability in every tool and the difficulty to use it and which is the best situation to use this tool ....
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3answers
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Verifying server software integrity?

I'm trying to brainstorm a security scheme for the problem of verifying server software integrity. The domain of this problem is Game Servers built on Valve's Source Dedicated Servers. These servers ...
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4answers
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Why don't ISPs filter on source address to prevent spoofing?

I'm under the impression that if all the ISPs were required to filter on the source IP address of all outbound packets, that spoofing would be reduced considerably. Are any ISPs implementing this ...
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2answers
911 views

What is a “pre-play” attack?

I understand what a replay attack is, but I keep reading about a pre-play attack. What is it? Is it when someone intercepts an unused message and blocks the sender so they can't finish using it, and ...
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2answers
3k views

How are mobile telephony networks like LTE and HSPA encrypted?

How are mobile telephony networks like LTE (4G) and HSPA (3G) encrypted? between what parts is the communication encrypted? who has access to the keys? is symmetric or asymmetric encryption used? is ...
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5answers
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Can voice chat be spied?

I wonder if voice chat (via public services like yahoo, google talk, skype, etc) is practically secure? Is it possible for the ISP or any middle point? I do not consider hacking the computers, but ...
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5answers
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Can I block based on Mac Address?

Incase of dynamic IP's the hacker can work around by taking a new IP or use a Proxy, is it possible to make a ban based on Mac Address ? I want to block at the Webserver level so that unwanted users ...
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3answers
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How to get MAC addresses of devices which are not in the network

Can I get MAC addresses of devices (mobile phones) which are near to my network but not connected to it? (Linux) I have been trying to get the MAC addresses of devices connected to my network through ...
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3answers
848 views

Would publishing a network diagram make the network less secure?

I have found some social networking sites that focus on sharing architecture (network maps and diagrams) and configuration. Does sharing this type of information decrease the security of my network? ...
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7answers
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IP address black list

My website has a black list of IP addresses. The web application, in some way, detects all invalid, suspicious influences to it and remembers IP address and denies any requests from that IP address. ...
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3answers
1k views

What security measures should be taken when running a Linux web server out of our office?

I am interested in running our company's web server from our local office. The office makes use of file sharing and NAS devices among other common office protocols. The worst case scenarios I've ...
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7answers
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What security implications are there for allowing outbound SSH traffic?

My school currently blocks outbound SSH traffic. Users inside the network cannot use Port 22, and attempting to make an SSH connection over another port is also blocked. (I'm assuming the firewall ...
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4answers
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Looking for botnet IP address feeds to protect against DDoS

I would like to get a live feed of botnet IP addresses delivered from a service and block them under certain conditions. Preferably community based/open source but open to looking at worthy commercial ...
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2answers
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Best way to report a foreigner attacker's ip to authorities?

I have been under attack last week and I was able to trace down the attacker and get his IP address. The attacker was located in Germany but I live out of Europe? From your experience what is the ...
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1answer
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Native rsync protocol security

Is the native rsync protocol (port 873) secure? Does it encrypt data or credentials? I'm planning on using rsync to store encrypted files in the cloud, I'm wondering whatever the password is ...
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1answer
5k views

Is WPA2 WiFi protected against ARP poisoning and sniffing?

Is WPA2 WiFi protected against ARP poisoning? If not, can the ARP poisoner decrypt the packets?
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6answers
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Automated tools for Cisco IOS config auditing? [closed]

Are there any automated tools for auditing config files exported from Cisco IOS devices? Free/Open Source is always nice, but anything that does the job would be of interest.
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4answers
769 views

What is the risk of a packet being sniffed when travelling over the internet without SSL/TLS?

We all know to use SSL/TLS to stop people eavesdropping on our connection, but how likely is it that an attacker will actually sniff your unencrypted password or cookie if you don't? If we exclude ...
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3answers
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What free tools or techniques exist to discover anomalies in network flows?

I have been using FlowMatrix. What do others do on the cheap?
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1answer
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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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4answers
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Is my network being sniffed?

Is there any way to find out if someone who is connected to my network is sniffing packets? There is a way with nmap if his card is in promiscuous mode but what if it is passive?
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1answer
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Bypassing hidden SSID and MAC filtering “protection”

I was browsing over this question and had some follow up questions from a practical perspective. What tools will show the SSID of an AP with the SSID set to hidden or broadcasting disabled? I have ...
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1answer
1k views

How can I detect real location of the user through their IP address?

There were many ways to detect the user's IP, for instance we could get it through a single click link or through any other medium of communication where we could get the user's IP. But the tedious ...
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4answers
884 views

Wireless Activity Monitoring for PCI DSS Compliance

In an effort to be PCI DSS compliant, I took a trustkeeper.net questionnaire. I failed the question that asks: Is the presence of wireless access points tested for by using a wireless analyzer at ...
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3answers
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How to best set up public WiFi without giving access to the rest of my network?

For reference, this is just for my home network. Anyway, I have quite a few of my neighbors ask me to share my internet with them. I'd really like to eliminate this "here's the password" portion ...
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4answers
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How to prevent network administrators from accessing USB drive

How can I prevent network administrators from accessing, mapping to etc. a USB drive that's in a PC on their network? I'm mainly concerned about files being edited or deleted.