Wednesday, 14 August 2019

Spot the Bait: a Lesson About Phishing



Written by Adrien Souyris

We’ve all experienced phishing - those annoying, sometimes dangerous emails attempting to trick us into giving away money or sensitive information. Most of them are clearly scams, but some are smarter and more difficult to spot. 

Symantec identified in 2018 that 54% of all emails were malicious (spam or phishing). As well as this, an average user receives 16 suspicious emails per month. More astoundingly, Verizon reports that 90% of breaches involve phishing.

So, who's behind these phishy emails? In short, anyone from amateur scammers to Russian GRU operatives and skilled cybercrime groups. Phishing is a cybercriminal's favourite tool, but why? Well, IT departments understand how important it is to build a cyber castle around the company's network; firewalls are everywhere which make it harder to attack company networks. And because we built castles, attackers invented a Trojan horse: phishing emails.

It is nearly impossible for machines to automatically distinguish between a legitimate and a well-crafted malicious email. IT and security departments can’t guarantee a phish-free inbox, and with each malicious email displayed to users comes the risk of someone inadvertently giving away the castle's keys. 

What are the remaining options, then? If they are informed and trained, staff make up a company's immune system by reporting phishing and helping the company fight back. 

Phishes of all sorts and colours

There are several types of phishing - angling, spear phishing, vishing, to name a few. The most common one is mass, automated phishing, which consists of creating generic phishing emails aimed at the largest possible number of recipients (usually millions). Even if only 1% of the recipients fall for it, that’s still 10,000 victims.

More targeted attacks are called spear phishing. These consist of selecting high-value, well-researched targets, finding out information such as their online habits, relations and hobbies, and then carefully crafting a high-quality phishing email to be sent to this recipient only. These methods are usually employed by skilled cybercriminals or state-sponsored hackers. Intermediate steps exist between these two, for instance by targeting a specific company, department, or group of people. And what is the intention behind phishing emails? Usually one of two things: assets (information or money) going out or malicious content going in.

In preparation for the former, a cybercriminal will attempt to lure the recipient into giving away the asset. The most basic method is the scam; for instance, the criminal masquerades as a legitimate service - PayPal, Gmail, OneDrive, SharePoint, etc. By disguising the email as a notification or security notice, the sender lures the recipient into clicking on a link. 




Behind this link hides a fake login page where the victim then gives away their credentials. To avoid suspicions, the fake login page relays the almost-identical page of the legitimate service. 




To perform the latter, phishers may include a malicious attachment to the email like a Word or Excel file with macros or a script file. Both macros and script files are a form of coding which can be abused to download malware onto a computer. Alternatively, the cybercriminal may use a malicious hyperlink; behind it hides a web page which will attempt to install malware on the device. From there, the cybercriminal can gain access to the user's files, emails, or use his position in the network to compromise other company assets. 

Avoid taking the bait: stay aware

Phishers use social engineering, the art of hacking people using predictable human behaviour, to trick email recipients into performing an action in their favour. Social engineering in phishing emails can take many forms, but the following techniques are usually employed in phishing: 
  • Masquerading: most of the time, phishing emails will be crafted to be misleading and impersonate something or someone else. For this purpose, the email will make use of attributes which are usual for the stolen identity, including writing style and font appearance, colour schemes, and URLs.
  •  A believable scenario: building on the stolen identity, phishing emails create a story. For example, HM Revenue & Customs sending an email about your latest tax return or a colleague reaching out about a project.
  • Sense of authority: by masquerading as an authority figure, such as a professional body or manager, cybercriminals attempt to pressure the recipient without causing suspicion.
  • Sense of urgency: cybercriminals will usually build up on this false authority with pressure and urgency to achieve the result before the recipient becomes suspicious. Using terms like ‘the request is urgent’, ‘a lack of action will result in <insert threat here>‘, etc. encourages the recipient to act fast.
  • Sense of trust: some phishing emails may attempt to look like they originate from someone/something you trust like a friend or colleague.

Spotting phishing URLs

One of the easiest ways of spotting phishing emails is to check the structure of the URL to which the email is trying to redirect you. Let's take our previous fake URL and introduce how domain names work. We'll read the URL from right to left.

A domain name is just like a Russian doll, each ‘.’ represents a layer of doll. Here, the ‘.org’ is the largest doll, and ‘myaccount.’ is the smallest one.

The best way to read a domain name is to spot the rightmost ‘.’ (before the succession of a ‘/’ if applicable). This is usually a ‘.com’, ‘.org’ or ‘.co.uk’. The domain name is to the left of this. Here, our domain is ‘ml-security’. The URL confuses users by introducing a misleading ‘myaccount.google.com’.

Another deception to keep in mind is best illustrated through another example:


In the URL above, suspiciouslink.com is disguised as accounts.google.com. If you click on a link, you should always make sure it sent you to a legitimate place.

Taken the bait by mistake?

All human beings are vulnerable to social engineering. By hitting the right spot, a skilled cybercriminal can hack anyone. If you suspect you’re a victim of phishing, here are the steps you should follow: 

  • Don't panic, this can happen to anyone.
  • Send an email without delay to your IT helpdesk or to your security team. A point of contact should always be available in your organisation for these incidents.
  • Do not delete anything, unplug anything or turn your computer off, unless instructed by security or IT personnel, as the evidence may be needed. You can flag the suspicious email as spam or phishing.
  • Pay attention to and report any further suspicious behaviour on your laptop and applications, such as freezes, slower performance, emails or files disappearing, mouse stutters, etc.

Take the test

Google created a tutorial test that shows the typical techniques used in phishing. Don't worry, it isn’t a phishing link.

You can find it here.

Thursday, 1 August 2019

The Power of Social Engineering Part Three; First Line of Defence



Written by Stuart Peck

In the previous two articles, we covered the fundamentals of social engineering and techniques used by attackers to great effect to gain unauthorised access to sensitive information. In this post, we are going to outline some of the defensive techniques you can develop to reduce your exposure to social engineering. Note that I did not say mitigate or remove risk, because the reality is that even the most hardened security professional can be social engineered; it’s a matter of timing and a well-researched and crafted pretext, that could lead to an attacker striking gold.

What this article aims to provide is a range of tactics that reduce the exposure from simplistic to advanced techniques used by attackers on a regular basis.

People-Centric Attack Vector Requires People-Centric Defence

If you are reading this then you may have spent years learning about infosec, attended a few training courses, maybe you hold a few certificates, and consider yourself adept at dealing with phishing and other social engineering attacks. Now let’s talk about compliance based “Security Awareness” training; on average, this is an annual or biannual exercise, usually online or through a Learning Management System, and derives little engagement from the employees. The key here is that infosec professionals spend many years learning their tradecraft, and yet we expect users to change behaviours, become adept at spotting and reporting phishing emails and other attacks in a 1-2-hour CBT (Computer Based Training) course.

Changing behaviours takes time; on average, over 3 months before new habits form and become normal working procedures. The key to affect change is to get user buy-in, which usually is very difficult unless your training is highly engaging and preferably face to face. It’s made even more difficult given security departments are typically small in comparison to the rest of the IT team and verses the actual headcount of the business. This is where developing programs that encourage champions is vital, where the security team can increase their footprint within each of the business units with a person who takes an active interest in promoting information security, training, and is essentially the human sensor for the infosec team.

Defence is Much More Than Just Training

Specifically identifying your high-risk groups of people in your organisation that are likely to be targeted by social engineers, and providing targeted training is a quick win, but it’s also important to provide a wider and longer term strategy that does not just involve annual Computer Based Training activity. Social engineering defence is the balance between Education, well enforced Policies and Technology. Here are a few ideas:

1)      Know who your targets are and invest in regular face to face training. Everyone is a potential target for social engineering, however, here are some high-risk groups:

·         Executive Assistants
·         Customer facing employees
·         IT / Developers
·         Marketing / social media
·         Finance / Payroll

2)      Understand the risks of oversharing; are your employees making themselves an easy target?

·         Monitor social media, especially Instagram / Facebook and provide guidance on what could expose the employees and the company to risk of being targeted
·         Make employees aware of the exposure and provide regular training on the risks of oversharing

3)      Specific and regular training on the risks of social engineering is vital, but in addition:

·         Provide policies that do not penalise those who report, but actively encourage engagement. Buy-in is a must!
·         Principles of trust but verify destabilise social engineering and can be highly effective
·         Segregation of duties for high-risk targets is vital!

4)      Technology, people, and process need to work in harmony; without this, social engineering will always be a risk

·         Ensure everyone has multi-factor or U2F to reduce risks from phishing and credentials stuffing
·         Put in place processes and technology that allows employees to easily report potential phishing scams
·         Gamification and simulated attacks work but naming and shaming does not

5)      Understand the risks and exposures

·         Policy and procedure review - does everyone know their responsibilities? How can you prove this?
·         Data Risk Assessment and Discovery - where is the critical data? How well protected is it? Who has access?
·         Incident Response – how effectively can you detect, react and respond to a social engineering attack?

6)      Attackers Don’t Care About Compliance

·         Prevent social engineering attacks by conducting risk assessments to spot & remediate potential weaknesses
·         Regularly test for weaknesses in people, process and technology. Test, remediate, repeat
·         Compliance training does not drive lasting change! Make training fun, engaging, and about the employee; give them the skills and tools to improve their own personal security posture, therefore massively reducing risk

In Summary

Social engineering has been around for an extremely long time, but technology has enabled it to scale at a rate never seen before. Existing strategies of annual training, unclear policies and reliance solely on technology to fix what is a very human problem, are clearly not working.

What’s required is a long term strategy where regular face to face training is invested in; safe behaviours are championed; reporting is encouraged; policies are clear, well defined, and presented in a way that normal employees can understand; and technology is used in a way to help deter, detect, react and respond to attacks that target the human.

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