REDBACK COUNCIL - RISC

How Common Attacks Are Being Blocked By Linux IPTABLES

  

ifcfg-eth0 file configuration

Here in this section I am going to discuss some common attacks can be done on any type of Linux machine and I will also describe that how they are being blocked by iptables.

ICMP Flood | Ping Traffic

This is also known as ping of death attack or an ICMP flood. One must block ping traffic by using iptables. One must block all ICMP incoming packets from outside connection. You can let it allow for your internal network.  Below command shows how ICMP flood can be dropped by using iptables.DROP is used for dropping packet.

iptables -A OUTPUT -p icmp --icmp-type 8 -j DROP

Drop incoming NULL Packet

Null packets should be dropped by following command:

iptables -A INPUT -p tcp --tcp-flags ALL NONE -j DROP

Drop incoming XMAS Packet

XMAS packets should be dropped by following command:

iptables -A INPUT -p tcp --tcp-flags ALL ALL -j DROP

Drop incoming Fragments Packet

Fragments packets should be dropped by following command:

iptables -A INPUT -f -j DROP

Drop SYN Packets

SYN packets should be dropped by following command:

iptables -A INPUT -p tcp ! --syn -m state --state NEW -j DROP

Thus we can use iptables in efficient way.

Use Google Reverse Image search to Detect Fake Facebook Profile Picture

Facebook is the biggest social networking website which we use to connect people we know and make new friends as well. But there are many scammers out there. So, it is very important to be aware of fake people on Facebook . There are thousands of fake profiles on Facebook which tries to trick people and get personal information. So, you should know how to check if the profile is fake.

Most of the times, boy create fake profile of girls with some random photos of pretty girl photo. If you receive friendship request from unknown girl or boy, you should first check the profile and photo to know if it is real. If you like the person by look, you should also check if the photo belongs to that profile. For this, use Google reverse image search.

If you are on Google Chrome, you can directly right click on profile picture and select "Search Google for this image" option.

If you are on some other browser, Copy image URL and open Google images . Here, select search by image option by clicking on camera icon in text box.

After searching by the image, if you see many Facebook and other profiles using the same profile photo with different name, the profile is fake. Most of the times, people use Google images to search pretty faces to put as profile picture on Facebook. So, this method will help you.

Sometimes, reverse image search does not help. In this case, you need to check how active the profile it? And how this person communicate with other people on posts and comments. Now, check the timeline of the profile to see the activity and user engagement. You will get an idea about the profile.

 Earlier this week, Facebook announced that it was going to start using all of that ever-so-illuminating app and website data it collects to serve us with more targeted ads. In other words, Facebook is getting ready to use your browsing history to benefit advertisers. Here's how to stop them.

Of course, just because you're getting some new (and highly necessary) controls over how Facebook shares your data doesn't mean it's going to stop collecting the data in the first place. So while we can at least somewhat limit how all of our salacious internet habits are being used, it doesn't mean the cache of data itself is going away.

What's more, the new feature is opt-out, so in order to keep your browsing history away from prying third-party eyes. You'll need to actively head over to the Digital Advertising Alliance hereand let them know you're not willing to share.

Note: if you're using AdBlocker Plus or anything else that disables cookies, you're going to need to turn that off before you'll be able to opt out.

Once there, you'll see the above screen. Select the "Companies Customizing Ads for Your Browser" tab, and scroll down until you see Facebook.

Click the little check box next to Facebook, and as long as you're here, feel free to scroll through and check off any other sites you'd like to stop forking over your most private internet deeds. Once you've clicked to your heart's content, hit "Submit."

Now, considering how many of us also use the Facebook app, you're probably going to want to do the same for your mobile device(s). For iOS users, open settings and go toGeneral>Restrictions>Advertising (under the "Privacy" section). Flip the switch for Limit Ad Tracking, and you're all set.

If you're using Android, go to Google Settings>Ads>Opt Out of Interest-Based Ads, and that's it—you're free to browse in peace.

Facebook advertisers won't be able to cater to you quite so creepily, and your privacy is left just that much more intact. Of course, that's not to say that Facebook's advertisers would do anything malicious with the data, but considering all that we do out on the internet's wild frontiers, better safe than sorry.