Questions tagged [routing]
Routing is the process of moving packets across a network from one host to another. It is usually performed by dedicated devices called routers.
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How can a webpage get the MAC address?
I was logged on to my router and filling out some information. I clicked a button and a field was automatically filled in with my computer's MAC address. How is this possible? Does it present a ...
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What are the security implications of enabling UPnP in my home router?
I found port forwarding entries in home router that I haven't manually configured. Is that because of UPnP?
Are applications simply able to tell the router to forward ports on their own? Are there ...
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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 traceroute ...
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How secure is binding to localhost in order to prevent remote connections?
Let's say we're running a service that's bound to localhost (127.0.0.1), and the goal is to only allow local clients (i.e. from the same machine only)
What techniques might be used to break this ...
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Access to a router's GUI
During a recent visit to a coffee shop, I noticed that they hadn't bothered changing their default user name and password for their router.
I realise that someone could log on and be annoying to ...
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Public DMZ network architecture
Years ago, when I was a student, a network security professor taught me in a class what a DMZ is. The architecture he used in his slides was similar to this one:
Now that I got employed, my boss, a ...
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What does the email header-line "message opened by mailclient" mean?
Today a Belgian MP claimed (backed up by a security expert) that her email headers show that her email was read during routing (text in Dutch).
The published screenshot of the headers highlights the ...
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Router password vs MAC filtering?
I just bought a Galaxy S4, and it didn't connect to the WIFI in my house (I have a 14$ router). After a bit of testing, I've decided to leave my connection open without a password, but added the ...
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Can home routers get infected?
I am behind a router(linksys that runs dd wrt on it) and I was infected with sality. I'm curious, can my router get infected too? If yes, how can I remove the infection?
I used the search bar but ...
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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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Attackers of Google DNS hijacking
As we know Google DNS server (8.8.8.8) in 14th and 15th March was hijacked in Sao Paulo. And subsequent to this event, BGPmon.org announced an alert.
Now, In a course assignment, we are asked to find ...
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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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Firewall defined Akamai IP Range [closed]
With obvious dangers of opening up a wide range of ips, does anyone know how I can get a source of IP ranges for Akamai?
When talking to Akamai they say 'not possible' which I find surprising.
I ...
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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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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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How can I stop this DOS attack?
I have this entry appearing constantly in my router logs:
[DOS Attack] : 5 [RST Scan] packets detected in last 20 seconds, source ip [xx.xx.xx.xx]
They just never stop. It doesn't seem to affect ...
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How is Tor secure despite being open source?
If Tor is open source (and thus its process of concealing your IP is known), then how does it keep anything secure? Couldn't someone look at the source code and figure out how to reverse the routing ...
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Is dd-wrt generally more secure than manufacturer's firmware?
I have been advised to use dd-wrt, for richness of features and heightened security.
The argument about security is that major manufacturers don't care much about the firmware, release with a lot of ...
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Vulnerabilities of pure NAT without firewall
Following some of the comments on this question, I was curious about the security vulnerabilities of NAT. There are similar threads here and here but they discuss router vulnerabilities rather than ...
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Security Services on Edge Router vs. Standard Firewall
If I can run a site to site VPN, NAT & Reflexive ACLs on a edge router (plus normal routing functions), what would be the use of running a stock firewall behind it?
For instance, Core Switch --> ...
8
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What is packet drop, packet loss and how Packet drop attack works?
I confused with the three terms:
Packet drop.
Packet loss.
Packet drop attack.
8
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1
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Is my ISP BGP/DNS hijacking?
I've noticed some very suspicious activity from my ISP.
Sometimes I would notice that when I ping google.com it would resolve to an IP which is owned by my ISP. I currently don't have an example ...
8
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Why does Tor use a new route every few minutes
As far as I know, Tor selects three new nodes every few minutes. What is the advantage of this?
The only thing I came up with was to prevent "Bad exit nodes" from viewing too much of your (hopefully ...
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Routing Protocol Encryption
As far as I know 'newer' versions of routing protocols support authentication between routers.
What about encryption and integrity checks? Some implementations like this one from Cisco use MD5, which ...
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Can the loopback interface be hijacked?
Inspired by this question I came up with this weird idea of making what that user actually wants to prevent. So, bear with me for a little bit:
Let's assume that for some reason we could make the ...
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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 syn-...
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Out-of-the-box Network Intrusion Appliance for non-Power User
First, let me apologize if any of this question is naive or beneath the scope of this board. Bear in mind the context and that I'm asking as an attempt to exhaust all resources.
Also, I understand if ...
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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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1
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Understanding OpenWRT LuCI Firewall Routing with VPN
I'm still fairly new to networking, and I'm having a little trouble grasping some concepts of the proper firewall rules I need to implement for my desired setup. I'm setting up a router with OpenWRT ...
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Ping Blocking: How to do? How to break?
I can access each page of a site through the browser (firefox). I can also see the ip and port address in firebug, but when I open cmd->ping site ->it says "request timeout".
I also ...
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How to track back a dynamic IP address?
Is there a way to trace back who was using a public dynamic IP address previously?
Would it be possible to find out the MAC address of the host using the IP address at a given time? (e.g., can you ...
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What are the security implications of net.ipv4.conf.eth0.route_localnet=1 / route_localnet?
sudo sysctl -w net.ipv4.conf.eth0.route_localnet=1
What are the security implications of route_localnet?
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Solaris: IP Spoofing Across Ethernet Ports
Given a Solaris machine with two network interfaces corresponding to the separate ethernet ports in the back.
0: 192.168.0.5/255.255.255.0
1: 192.168.1.5/255.255.255.0
with /etc/defaultrouter set to ...
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Two SSIDs on same Access point- not good?
If I were to offer two networks (one for trusted users and one to visitors) on one physical access point, is this dangerous because a visitor could compromise the trusted network across via the ...
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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 ...
6
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3
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Forensics on a SOHO router
I am interested in how reliable the information determined from doing forensics on a SOHO router is. Most of these routers don't seem to be very advanced, so I question if it would be possible to ...
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Recent Fritz Box exploit
Background info:
About 50% of the ADSL and cable internet access in Germany (and presumably parts of the EU) goes over AVM Fritz routers, either verbatim or rebranded as e.g. "1&1 Home Server" or ...
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How can I be sure that an intranet app is absolutely not accessible from the internet?
I am developing an intranet application using Apache/MySQL. The server hosting it does not have a public IP address itself, but can access the internet through a router. There is not any sensitive ...
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incoming packets in server
I have enabled iptables logging for packets coming from the outside
-A INPUT ! -s 192.168.218.0/24 -j LOG
Now i am seeing lots of incoming packets from unknown addresses
Jun 5 14:54:56 localhost ...
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Best way to push data to a client without being blocked by firewall
I'm asking this question here since I think people on this forum
probably have the best knowledge of firewalls and routers.
Say I'm designing a multi-player game and I want to push data to the client ...
5
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4
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Encryption of headers in IPsec tunnel mode
I am learning about IPsec's transport and tunnel modes. I understand that transport mode encrypts only the payload of an IP packet and is used for communication between two entities that both ...
5
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2
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How can I obtain the internal IP of a computer behind NAT but reachable via certain TCP port?
I want to obtain internal IP of a remote computer behind a NAT that I can reach by using some port, say myhost.farfar.away port 11122TCP:
C:\>telnet myhost.farfar.away 11122
SSH-2.0-OpenSSH_6.6....
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do different subnet masks on home network provide any security?
So I have two routers on my home network: one is provided by my ISP, and the other is my private router.
Router A- ISP router: 192.168.1.x
router B- private router: 192.168.2.x
Clients on my ...
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Sending Probe Request Frames | Receving Probe Response -- Scapy
OBJECTIVE
Send probe request frame subtype=4 and receive probe response subtype=5 with Scapy
Ultimate goal is to detect access points nearby via Scapy ( not by sniffing beacon frames )
The object ...
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What is the simplest way to prevent adding a new default route via dhcp?
I have a corporate network to which remote access is provided via openvpn. Customers include a variety of devices (laptops, smartphones).
These devices running software that accesses corporate ...
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2
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Provider can access my local network?
I recently talked with my ISP about many things, basically related to my (little) company security, this guy is a networking guru to me, but he did a strange thing that worries me. Basically I have a ...
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How to bypass restrictive mac address filtering on home network (not malicious)
Background
A short sketch of my situation before I formulate my question: I am on a large home network, which is privately administered by a couple of admins. The network consists of a lan and a ...
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Can someone take money out of my account with just my Account & Routing number?
I had recently given someone my account number and routing number to deposit money into my checking account. They owed me money I had lent and said this would be the easiest way for them to do it. I ...
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Access router if you don't know password
At home I have a wireless cisco router. Unfortunately I wasn't smart to change its ip or passwords. So anyone who is connected to it can access 192.168.0.1 and log in as admin using password admin and ...
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Does "loose source and record route" drop the source address?
Is the source IPv4 address lost when a person uses "loose source and record route" and the destination address is put before the end of the list of addresses through which routing should occur?
It ...