Secure Your WIFI Network....
Friends we have something very Important to share with you about wireless Points (WIFI) .. :)
The stuff about wireless will come out to you in 3 different parts ( TO
MAKE ENOUGH Posts . Cause I am out of Ideas and I am busy with Studying
) Hope you enjoy reading them and ofcrs dnt forget to share ! )
IMPORTANT STUFF ABOUT WIRELESS :
PART 1 :
Wireless networks broadcast their packets using radio frequency or
optical wavelengths. A modern laptop computer can listen in. Worse, an
attacker can manufacture new packets on the fly and persuade wireless
stations to accept his packets as legitimate.
The step by step procerdure in wireless hacking can be explained with help of different topics as follows:-
1) Stations and Access Points :- A wireless network interface card
(adapter) is a device, called a station, providing the network physical
layer over a radio link to another station.
An access point (AP) is a station that provides frame distribution service to stations associated with it.
The AP itself is typically connected by wire to a LAN. Each AP has a 0
to 32 byte long Service Set Identifier (SSID) that is also commonly
called a network name. The SSID is used to segment the airwaves for
usage.
2) Channels :- The stations communicate with each other
using radio frequencies between 2.4 GHz and 2.5 GHz. Neighboring
channels are only 5 MHz apart. Two wireless networks using neighboring
channels may interfere with each other.
3) Wired Equivalent Privacy (WEP) :- It is a shared-secret key
encryption system used to encrypt packets transmitted between a station
and an AP. The WEP algorithm is intended to protect wireless
communication from eavesdropping. A secondary function of WEP is to
prevent unauthorized access to a wireless network. WEP encrypts the
payload of data packets. Management and control frames are always transmitted in the clear. WEP uses the RC4 encryption algorithm.
4) Wireless Network Sniffing :- Sniffing is eavesdropping on the
network. A (packet) sniffer is a program that intercepts and decodes
network traffic broadcast through a medium. It is easier to sniff
wireless networks than wired ones. Sniffing can also help find the easy
kill as in scanning for open access points that allow anyone to connect,
or capturing the passwords used in a connection session that does not
even use WEP, or in telnet, rlogin and ftp connections.
5 )
Passive Scanning :- Scanning is the act of sniffing by tuning to various
radio channels of the devices. A passive network scanner instructs the
wireless card to listen to each channel for a few messages. This does
not reveal the presence of the scanner. An attacker can passively scan
without transmitting at all.
6) Detection of SSID :- The
attacker can discover the SSID of a network usually by passive scanning
because the SSID occurs in the following frame types: Beacon, Probe
Requests, Probe Responses, Association Requests, and Reassociation
Requests. Recall that management frames are always in the clear, even
when WEP is enabled.
When the above methods fail, SSID discovery is done by active scanning
7) Collecting the MAC Addresses :- The attacker gathers legitimate MAC
addresses for use later in constructing spoofed frames. The source and
destination MAC addresses are always in the clear in all the frames.
8) Collecting the Frames for Cracking WEP :- The goal of an attacker is
to discover the WEP shared-secret key. The attacker sniffs a large
number of frames An example of a WEP cracking tool is AirSnort ( http://airsnort.shmoo.com/ ).
9) Detection of the Sniffers :- Detecting the presence of a wireless
sniffer, who remains radio-silent, through network security measures is
virtually impossible. Once the attacker begins probing (i.e., by
injecting packets), the presence and the coordinates of the wireless
device can be detecte
10)
Wireless Spoofing :- There are well-known attack techniques known as
spoofing in both wired and wireless networks. The attacker constructs
frames by filling selected fields that contain addresses or identifiers
with legitimate looking but non-existent values, or with values that
belong to others. The attacker would have collected these legitimate
values through sniffing.
11) MAC Address Spoofing :- The
attacker generally desires to be hidden. But the probing activity
injects frames that are observable by system administrators. The
attacker fills the Sender MAC Address field of the injected frames with a
spoofed value so that his equipment is not identified.
12) IP
spoofing :- Replacing the true IP address of the sender (or, in rare
cases, the destination) with a different address is known as IP
spoofing. This is a necessary operation in many attacks.
13) Frame Spoofing :- The attacker will inject frames that are valid but whose content is carefully spoofed.
14) Wireless Network Probing :- The attacker then sends artificially
constructed packets to a target that trigger useful responses. This
activity is known as probing or active scanning.
15) AP Weaknesses :- APs have weaknesses that are both due to design mistakes and user interfaces
16) Trojan AP :- An attacker sets up an AP so that the targeted station
receives a stronger signal from it than what it receives from a
legitimate AP.
17) Denial of Service :- A denial of service
(DoS) occurs when a system is not providing services to authorized
clients because of resource exhaustion by unauthorized clients. In
wireless networks, DoS attacks are difficult to prevent, difficult to
stop. An on-going attack and the victim and its clients may not even
detect the attacks. The duration of such DoS may range from milliseconds
to hours. A DoS attack against an individual station enables session
hijacking.
18) Jamming the Air Waves :- A number of consumer
appliances such as microwave ovens, baby monitors, and cordless phones
operate on the unregulated 2.4GHz radio frequency. An attacker can
unleash large amounts of noise using these devices and jam the airwaves
so that the signal to noise drops so low, that the wireless LAN ceases
to function.
19) War Driving :- Equipped with wireless devices
and related tools, and driving around in a vehicle or parking at
interesting places with a goal of discovering easy-to-get-into wireless
networks is known as war driving. War-drivers (http://www.wardrive.net/)
define war driving as “The benign act of locating and logging wireless
access points while in motion.” This benign act is of course useful to
the attackers.
Regardless of the protocols, wireless networks will
remain potentially insecure because an attacker can listen in without
gaining physical access.
TIPS TO SECURE YOUR WIFI
1) Change Default Administrator Passwords (and Usernames)
2) Turn on (Compatible) WPA / WEP Encryption
3) Change the Default SSID
4) Disable SSID Broadcast
5) Assign Static IP Addresses to Devices
6) Enable MAC Address Filtering
7) Turn Off the Network During Extended Periods of Non-Use
8) Position the Router or Access Point Safely
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