Network Security - securing network infrastructure and connections

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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 ...
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8answers
804 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 ...
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3answers
631 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 ...
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4answers
340 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.
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5answers
27k views

Multiple VPN clients in parallel

If I were to run more than one VPN clients on my machine, simultaneously, what risks would be involved? E.g. are there technical conflicts, such that it wouldn't work right? Could there be ...
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3answers
6k 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 ...
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3answers
822 views

Can an attacker “simulate” a private IP address?

I have a SSH server with a rule that does not allow password connections outside the local network. So people already on the local network, either physically or via VPN, are allowed to connect with ...
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2answers
9k views

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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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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9answers
574 views

Which factors should you take into account when deciding whether users should be informed of a penetration test?

Say you are conducting a penetration test of an internal network. The internal network comprises of workstations, servers and company and contractor laptops. In an ideal world, the penetration test ...
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2answers
17k 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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1answer
838 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 ...
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1answer
204 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 ...
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3answers
826 views

How did the spammers get this address?

A few months ago I configured a test mail server on Amazon AWS, all legit. I used a new address to my catchall-domain (something similar to, but not exactly, ...
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2answers
556 views

How do you Secure VOIP in a large organization

As part of a large organization looking to implement VoIP, to get on the bandwagon of savings and converged network focus, I'm being asked to look at the security concerns to develop a policy to help ...
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2answers
684 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 ...
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3answers
2k views

Secure PXE network OS installation

How can one make sure that when PXE is being used to boot a remote operating system, that the data being sent is encrypted (or at the very least that integrity is maintained)? Would it be possible to ...
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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 ...
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6answers
2k views

Dual Router Configuration

I have a home network that was hacked into recently. The people that got into my network actually accessed my personal files and although I cannot prove it, I think they might have stolen some of ...
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3answers
13k 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 ...
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8answers
29k views

How to block some websites and torrent usage in a small office?

In my office there are approaximately 25 systems are connected through network and all having internet accessibility.but some people are missusing this facilities like downloading films from torrent ...
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5answers
7k 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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10answers
675 views

networking and security

I'm trying to pick up networking security within a reasonable amount of time. I'm not specifically looking to learn about all the little tools that are available (although I do want to know about ...
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1answer
1k views

Does restricting the names of computers allowed to connect to a wifi network provide any security

In response to a statement elsewhere that MAC address filtering was essentially useless for protecting a wifi network because it was trivially by passable by network attack tools, I was asked if the ...
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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. ...
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2answers
4k 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 ...
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2answers
357 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 ...
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2answers
12k 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 ...
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4answers
8k 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?
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3answers
4k 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 ...
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1answer
1k views

Is it possible to recognise and prevent MitM attacks on devices which use self-signed SSL certs?

I use both Linux and Windows at work on a large enterprise LAN. The majority of the network configuration is out of my reach. Certain SaaS applications that are hosted locally on the enterprise LAN, ...
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3answers
6k 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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3answers
811 views

Is IPv6 with NAT less secure than IPv4?

This is a follow up to a snippet from another answer. There, user Ninefingers writes: (...) only allow outbound connections, ever. Do this in spite of NAT as IPv6 will make those NAT defences ...
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6answers
2k views

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
4k views

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
695 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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3answers
468 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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2answers
12k views

Recommended Cipher Suites for TLS 1.0, 1.1 and 1.2

There are a lot of cipher suites defined in the in the specifications itself of TLS 1.0, 1.1 and 1.2. And furthermore, there exist RFCs which add even more cipher suites to a specific version (e.g. ...
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1answer
14k views

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 ...
8
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1answer
485 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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2answers
1k views

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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2answers
247 views

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 ...
8
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1answer
240 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 ...
8
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1answer
186 views

Deanonymizing users by introducing structured delays to the network?

Here is a scheme for deanonymizing a user that I've been thinking about, just out of curiosity. I tried searching for it but didn't find much. Does this technique have a name? Are there any papers or ...
8
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1answer
1k views

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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5answers
3k views

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 ...
8
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4answers
26k 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 ...
8
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1answer
292 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
441 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 ...
8
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1answer
792 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 ...