Social engineering

Attacks could be divided into two categories based on the way how the attack works. Passive attacks are attacks which do not modify the information or the system. Such attacks are mainly used for gathering information. Active attacks try to get access to the system so that it would be possible to affect or modify it. Thus, wiretapping is considered to be passive attack in case information is not modified due to wiretapping. However, using malware or exploiting vulnerabilities to breach / infect computer networks is considered to be an active attack method.

When people read about attacks against computer systems or about data breaches then often they think that the attacker was an evil hacker who used malicious programs or sophisticated tools in order to breach the systems or leak the data. Actually, this assumption might not be correct as the attacker looks for the weakest link in the system when planning the attack and usually the weakest link is the human. Thus, many attacks are designed to abuse the psychological weaknesses in order to gain access to information or computer systems. Attacks against the human weaknesses do not require sophisticated tools and are cheap to implement. Such attacks are classified with the term social engineering.

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Social engineering techniques

Social engineering uses the human weaknesses in order to get access to the desired resources. The attacker might use social engineering to get direct access to the resources, e.g., by using an employee to infect the company's inner network. However, the attacker might also get access to the resources indirectly if the employee gives out confidential information. One might think that it is difficult to get an employee to trust a stranger and therefore such attacks would be unlikely but unfortunately this is not true. A good social engineer starts by going through all of the background information about the company and its employees in order to find a good pretext or to find a weak spot in system.

Gathering information about the target

The attacker needs as much information about the target as possible. It is probably important to know the inner structure of the organization and the details about how the organization operates. In addition, it would be very useful to know which kind of software is used by the organization and which security measures are used. So, how could the attacker get access to such information?

First all legally available information will be gathered. Probably the website of the organization gives some useful information to the attacker but much more information could be found by using search engines as they might store cached information that can not be directly accessed anymore. In addition, the employees might leak information about the employer in blogs or in social media. It might also be possible to apply for a job in the organization in order to gather additional information during the job interview.

When the initial research is done then the attacker could start to use illegal means for gathering information. It might be possible to follow an employee of the targeted organization in order to collect information from phone calls or conversations. It might be possible to gather important details just by sitting next to the targeted employee in a restaurant. Another option for the attacker is to pretend to be someone else in order to gain more information about the target. However, much more information could be gathered if the attacker would be able to enter the areas of the organization that are restricted to the public. One way to get into the restricted areas is to use tailgating, i.e., to follow someone through the door. Tailgating is not allowed in many companies and this means that the employees that enter the restricted area have to always use their ID. Shoulder surfing might also work, i.e., once the attacker is able to enter the facilities it might be possible to walk around and see what can be seen from the screens of the employees. A good place for finding information is the dumpster of the organization that is being targeted. This method is called dumpster diving and this is the main reason why many companies lock their dumpsters.

Apple has signs on the doors that prohibit tailgating, source.

Analyzing the gathered information to find a weak spot

Once the attacker has enough information about the target it is possible to start planning the real attack. The goal of an attacker might be to access some classified information or to infect a computer in the inner network in order to gain remote access. The weak point might be an employee that could be manipulated using the gathered information. However, it might be possible that the attacker has gathered enough information which allows to get access to the facilities in order to infect the inner network. For example, some companies may be less strict about checking delivery men and people who do maintenance related work.

Implementing the attack

The attack might be done remotely over the phone or email by using the gathered information in order to manipulate the employees. For example, one might call to an employee and pretend to be from the IT-service and ask the employee to reveal information about the software or even to reveal the password. Specially crafted emails could be used to gather confidential information from the employees or to infect their computers. The attacker may infect the computer of the employee by creating a malicious web page and tricking the employee to click on the link in an innocent looking email. An easily usable trick that helps to infect the company network is to drop an infected USB stick near the organization such that the employees would find the USB stick. The USB stick might contain files like salaries_2018.xls that trick the employees to open the infected files in their computers.

source (link broken currently)

A good overview of social engineering techniques, information gathering, psychological principles and attack vectors can be found from The Social Engineering Framework.

Some real life examples of social engineering:

How to protect yourself or the employees from social engineering

The most important factor in avoiding damage by social engineering is the awareness of the employees. There are no security features that can protect the employee from social engineering if the employee does not know what social engineering is and how it is used. Therefore, the employees have to be trained to notice suspicious behavior.

In addition, the organization has to have a proper security policy which specifies how the employees have to act in certain situations. Should the employees give the delivery man or service personnel access to the building and how should they determine that the person really is who he / she claims to be. The security policy also has to state who has the responsibilities and who should be contacted in case something suspicious happens.

Phishing

In case of a phishing attack, the attacker tries to win his victim's trust in order to make the victim do what he wants: either click on a link, download some malicious software or give out information.

Phishing attack in Dilbert comic. (source)

Phishing methods:

Sending an e-mail with a text that persuades the receiver to click on a link in that e-mail. Such links may look like belonging to a normal service: https://www.your-bank.com/, but in reality take the victim to a page controlled by the attacker. This web page may try to install malware by using potential web browser's vulnerabilities.
Also changing the order of subdomain in a web page address is a common method for misguiding users. For example, a web page at www.ut.courses.ee would probably not be controlled by University of Tartu but rather by someone controlling the courses.ee second level domain. Remember that subdomain names are to the left of the second level domain name. Going from left to right means going up in the domain name hierarchy until reaching the top level domain (com, eu, ee, ...).
There are several tricks that are based on text encoding. For example, it is possible to reverse the order of text by using a special unicode symbol (u202e) that is used for Arabic / Hebrew. Also, some letters in different encodings appear very similar to the letters in latin alphabet but for the computer it is a totally different letter, this was demonstrated in the following blog post: Phishing with Unicode Domains.
If the attack is targeting a specific victim (called spear phishing), the attacker may first perform a background search on the intended victim to choose the right attack vector or gather information for the pretext.

A small and simple infographic showing how a Phishing attack happens. (Original source not available anymore)

Statistics

In a report by RSA it was estimated that in 2012 the total losses caused by phishing attacks were about 1.5 billion dollars. However, the significance of the phishing attacks continues to grow. The estimated losses for 2014 are three times bigger than the losses in 2012. RSA estimated that phishing caused about 4.5 billion in losses for global organizations in 2014.

Phishing attacks are also used in Estonia. In the 2013 report by national information systems authority it was written that phishing emails were used to attack the employees of Elisa, Elion, Estonian University of Life Sciences, University of Tartu and EENet. The quality and quantity of phishing attacks has increased as reported by the corresponding reports for the following years 2014, 2015, 2017. However, the RIA report for 2018 mentioned that: "– for example, we have worked with our partners and Estonian service providers to quickly detect and take down phishing websites. As a result, the number of successful phishing incidents in Estonia has decreased significantly."

Social Engineering Infographic, source.

Recent phishing attacks

Often the employees and students of the University of Tartu get emails which state that the university mailbox is starting to get full and one has to either connect the IT-service or log in to the mailbox in order to solve the problem. However, the trick is that a link is given to a fake website which looks like the real university mailbox. In addition, such mails might contain the request to send the username and password of the account to the fake IT-service. Most of these emails used to be machine translated which meant that they contained a lot of mistakes but recently some phishing mails have appeared that are written in correct Estonian.
In 2014 people got phone calls from someone who claimed to work for Microsoft. The attacker instructed the victims to install special software (malware) to their computers in order to increase their security.
Phishing attacks have been used to ask for money. One popular method is to hijack a mail account and then contact the friends or family of the account owner and tell them that an accident has happened and therefore some money has to be transferred to the given account. This attack method could work well for people whose children live abroad.
Example about the misusage of Google ads: Kraken Phishing Warning.
How Hackers Broke Into John Podesta and Colin Powell’s Gmail Accounts
In January 2015 an email was sent by someone who claimed to be from the Estonian Tax and Customs Board. The email contained information on the tax returns and asked to navigate to the linked webpage in order to fill in the tax returns form. The email itself was not written in correct Estonian but the fake website looked almost like the real website of the Estonian Tax and Customs Board. However, the url of the website was different and also the website contained a form which asked for the credit card number in order to get the tax return. The fake website can be seen from the following screenshot.

Infoturve 2018/19 sügis