COVID-19 continues to significantly embolden cybercriminals’ phishing and fraud efforts, according to research from F5 Labs.
The report found that phishing incidents rose 220% during the height of the global pandemic compared to the yearly average. The number of phishing incidents in 2020 is now set to increase 15% year-on-year, though this could soon change as second waves of the pandemic spread.
The three primary objectives for COVID-19-related phishing emails were identified as fraudulent donations to fake charities, credential harvesting and malware delivery.
Attackers’ brazen opportunism was in further evidence when certificate transparency logs (a record of all publicly trusted digital certificates) were examined.
The number of certificates using the terms “covid” and “corona” peaked at 14,940 in March, which represents a massive 1102% increase on the month before.
“The risk of being phished is higher than ever and fraudsters are increasingly using digital certificates to make their sites appear genuine,” said David Warburton, Senior Threat Evangelist at F5 Labs.
“Attackers are also quick to jump onto emotive trends and COVID-19 will continue to fuel an already significant threat. Unfortunately, our research indicates that security controls, user training and overall awareness still appear to be falling short across the world.”
Names and addresses of phishing sites
As per previous years’ research, fraudsters are becoming ever more creative with the names and addresses of their phishing sites.
In 2020 to date, 52% of phishing sites have used target brand names and identities in their website addresses. By far the most common brand to be targeted in the second half of 2020 was Amazon.
Additionally, Paypal, Apple, WhatsApp, Microsoft Office, Netflix and Instagram were all in the top 10 most frequently impersonated brands.
By tracking the theft of credentials through to use in active attacks, criminals were attempting to use stolen passwords within four hours of phishing a victim. Some attacks even occurred in real time to enable the capture of multi-factor authentication (MFA) security codes.
Meanwhile, cybercriminals were also got more ruthless in their bid to hijack reputable, albeit vulnerable URLs – often for free. WordPress sites alone accounted for 20% of generic phishing URLs in 2020. The figure was as low as 4,7% in 2017.
Furthermore, cybercriminals are increasingly cutting costs by using free registrars such as Freenom for certain country code top-level domains (ccTLDs), including .tk, .ml, .ga, .cf, and .gq. As a case in point, .tk is now the fifth most popular registered domain in the world.
Hiding in plain sight
2020 also saw phishers ramp up their bid to make fraudulent sites appear as genuine as possible. Most phishing sites leveraged encryption, with a full 72% using valid HTTPS certificates to seem more credible to victims. This year, 100% of drop zones – the destinations of stolen data sent by malware – used TLS encryption (up from 89% in 2019).
Combining incidents from 2019 and 2020, 55.3% of drop zones used a non-standard SSL/TLS port were additionally reported. Port 446 was used in all instances bar one. An analysis of phishing sites found 98.2% using standard ports: 80 for cleartext HTTP traffic and 443 for encrypted SSL/TLS traffic.
The future of phishing
According to recent research from Shape Security, which was integrated with the Phishing and Fraud report for the first time, there are two major phishing trends on the horizon.
As a result of improved bot traffic (botnet) security controls and solutions, attackers are starting to embrace click farms.
This entails dozens of remote “workers” systematically attempting to log onto a target website using recently harvested credentials. The connection comes from a human using a standard web browser, which makes fraudulent activity harder to detect.
Even a relatively low volume of attacks has an impact. As an example, Shape Security analysed 14 million monthly logins at a financial services organisation and recorded a manual fraud rate of 0,4%. That is the equivalent of 56,000 fraudulent logon attempts, and the numbers associated with this type of activity are only set to rise.
Researchers also recorded an increase in the volume of real-time phishing proxies (RTPP) that can capture and use MFA codes. The RTPP acts as a person-in-the-middle and intercepts a victim’s transactions with a real website.
Since the attack occurs in real time, the malicious website can automate the process of capturing and replaying time-based authentication such as MFA codes. It can even steal and reuse session cookies.
Recent real-time phishing proxies in active use include Modlishka2 and Evilginx23.
“Phishing attacks will continue to be successful as long as there is a human that can be psychologically manipulated in some way. Security controls and web browsers alike must become more proficient at highlighting fraudulent sites to users,” Warburton concluded.
“Individuals and organisations also need to be continuously trained on the latest techniques used by fraudsters. Crucially, there needs to be a big emphasis on the way attackers are hijacking emerging trends such as COVID-19.”