Network Security - securing network infrastructure and connections

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11
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4answers
319 views

What free tools or techniques exist to discover anomalies in network flows?

I have been using FlowMatrix. What do others do on the cheap?
10
votes
5answers
2k views

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 ...
10
votes
4answers
8k 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.
10
votes
6answers
421 views

Should we configure all devices to never request SSL 2.0, and reject it if offered?

In an effort to reduce man in the middle attacks, when will it be (or was it) an industry accepted practice to reject SSL 2.0 connections on the client and server side? Is configuring this on a proxy ...
10
votes
7answers
2k views

Alternative to VPN

We have a network that is completely closed to the outside world. It needs to be. Problem is we need to remote into a server on this network once in a blue moon for diagnostics. We've discussed ways ...
10
votes
4answers
2k views

How can an access point spoof me into connecting?

I was reading through the answers of the question "How can I ensure that I connect to the right wireless Access Point?" and was wondering how it is possible for an access point to imitate another wifi ...
10
votes
2answers
7k views

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 ...
10
votes
3answers
12k views

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 ...
10
votes
3answers
635 views

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 ...
10
votes
2answers
514 views

How were weak passwords brute forced in github?

Github faced a brute force password-guessing attack recently that involved "nearly 40K unique IP addresses". Passwords were also "stored properly" using bcrypt, (salt + hashed). Given that bcrypt ...
10
votes
5answers
16k views

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 ...
10
votes
7answers
3k views

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 ...
10
votes
4answers
4k views

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 ...
10
votes
5answers
1k views

What firewall settings on a Macintosh are the most restrictive, while still permitting casual internet use?

I don't want this to be subjective, so I'll try to make the requirements as clear as possible. On a Mac with Snow Leopard, how can I set up the firewall rulesets that allow ONLY: Using the internet ...
10
votes
1answer
3k views

Backtrack 5 in a VM - Why bridged networking over NAT?

When running Backtrack 5 from a VM, it is recommended to use the bridged networking option instead of the NAT networking option? How does it affect the usage of Backtrack - port scanning, ...
10
votes
4answers
2k views

Why don't ISPs filter on source address to prevent spoofing?

I'm under the impression that if all the ISP's were required to filter on the source IP address of all outbound packets, that spoofing would be reduced considerably. Are any ISPs implementing this ...
10
votes
3answers
439 views

Tools needed to setup a paranoid remote backup server

I'm a system admin with little security experience. I want to schedule the copying of our backups to protect our data in case of fire. The best solution would be to copy the data onto a new ...
10
votes
2answers
653 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 ...
10
votes
2answers
229 views

Online SQL Server database for a Business app. Security considerations

A business application works with a SQL Server database. A SQL Server 2008 is installed on one of the computers of the local network. Technically this app works OK if the server computer with the SQL ...
10
votes
3answers
11k views

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 ...
9
votes
3answers
2k views

Is it possible that authorities can't block a certain website

I was watching a very recent TV show, the FBI agent told the police that there is no way for anybody to block a live stream of a pedophile torturing a kid nor to trace it. Even when it's being ...
9
votes
5answers
7k views

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 ...
9
votes
3answers
681 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? ...
9
votes
8answers
742 views

Battling Malware without spending money

Our environment consists of about 80 users running Windows 7. Previous to me showing up as a full time IT employee, the company had contracted an outsource IT solution. As part of their set up, they ...
9
votes
3answers
536 views

Is secure Caller ID possible for SIP / VOIP?

Is there any way (standard, proposed or draft) that will allow for secure Caller ID over SIP / VOIP networks? I have constantly heard that Caller ID is insecure when used over these services. Can ...
9
votes
4answers
297 views

What are the main security considerations that must be taken into account if you intend on creating a (localised) whistleblower website?

Also: Is it something that can be achieved with limited funds? I ask because I am intrigued by the obstacles that are in place.
9
votes
1answer
2k views

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 ...
9
votes
6answers
10k views

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.
9
votes
3answers
4k views

Security measures for a WiFi access point?

I am planning to purchase a program that comes with an App that allows you to control the program via phone. The developer told me that the connection will be done via an extra WIFI box connecting to ...
9
votes
2answers
10k 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 ...
9
votes
2answers
2k views

Bypassing a reverse proxy/NAT

Reverse proxies and NAT would seem to obscure a network behind such technologies to the point where it would be hard if not impossible to identify ports open and services running. Given that many ...
9
votes
1answer
407 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 ...
9
votes
1answer
507 views

Checksums do not match when I download file over http

Just for the test I did the following: Downloaded a page from wikipedia via wget on remote server and named the file test.dat. Then I executed md5sum. I download the file via http and check it back ...
9
votes
1answer
171 views

Long running SMTP session

I recently noticed an SMTP session on my server which started when a remote host connected but never seemed to result in any emails being delivered. I could see that it was probably a SPAM site and so ...
9
votes
1answer
1k views

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

As the title says really, 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 it's own IP ...
9
votes
1answer
2k views

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 ...
9
votes
2answers
1k views

Malware known to use port knocking to evade detection by network scanners?

Are there any known cases of malware in the wild that utilize port knocking on a backdoor to evade detection by network scanners?
9
votes
2answers
541 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 ...
9
votes
2answers
588 views

How to implement secure device identification in a for-pay wifi router to prevent usage fraud?

After reading this question about how for-pay wifi routers identify specific devices it got me thinking about what a secure alternative might be. I know that certain research has focused on ...
9
votes
4answers
1k views

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
votes
3answers
10k 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 ...
8
votes
4answers
24k views

Tips for a secure iptables config to defend from attacks. (client side!)

Own examples: ############### # KERNEL PARAMETER CONFIGURATION # PREVENT YOU SYSTEM FROM ANSWERING ICMP ECHO REQUESTS echo 1 > /proc/sys/net/ipv4/icmp_echo_ignore_all # DROP ICMP ECHO-REQUEST ...
8
votes
3answers
15k views

How does “traceroute over TCP” work, what are the risks, and how can it be mitigated?

There is a utility called tcptraceroute, and this enhancement called intrace that is used just like a standard traceroute, but it works over TCP. How is the syn flag in TCP used to achieve ...
8
votes
4answers
3k views

extract from pcap all protocols found

I have some pcap files, and i would like just to get a list of protocols that are present on that pcap file. I would like it in a batch mode, not using wireshark I think tshark is able to do it, but ...
8
votes
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. ...
8
votes
2answers
3k views

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 ...
8
votes
2answers
320 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 ...
8
votes
4answers
6k 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?
8
votes
2answers
10k views

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 ...
8
votes
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 ...