X-Labs
Avril 21, 2020

Three-Month Trend Analysis: COVID and Coronavirus-Themed Web and Email Traffic

Carl Leonard Principal Security Analyst
Stuart Taylor Sr. Director, Security Labs

Forcepoint X-Labs is the custodian of threat and behavioral intelligence at Forcepoint. In analysing anonymized recent web and email traffic we have observed interesting trends generated by our global customer base. This analysis focussed on traffic relating to keywords of “Corona” and “COVID.”  We share our observations below to show how the behavior of cybercriminals and your own people have changed in response to the situation in which we all now find ourselves.

Methodology

  • Web and email traffic processed by our Cloud Web Security and Cloud Email Security products was analysed to surface trends of the last 3 months (19 January 2020 to 18 April 2020 inclusive).
  • We sought keywords of COVID and Corona in URLs accessed directly over the Web or embedded with an email.
  • The analysis was applied to a global dataset of Forcepoint customers.
  • Data was anonymized (counts only, no attribution) to protect the privacy of our customers as per our approach to “Privacy-by-Design.”

Highlights

  • The analysis shows that cyber criminals are opportunists seeking to piggyback on the public’s interest in COVID-19 and Coronavirus, as described recently in our Malware Author and Scammers post.
  • Brand new COVID and Coronavirus-themed websites have been registered and activated for both legitimate and illegitimate means.
  • Employees’ interest in COVID and Coronavirus-themed websites peaked in mid-March, correlating with the enactment of “lockdown” measures by governments around the word.
  • We saw a rise in unwanted emails (malicious, spam or phishing) containing embedded URLs using the keywords of COVID or Corona from negligible values in January 2020 to over half a million blocked per day the end-of-March onwards.
  • Note the dip in activity at weekends as is usual with active spam campaigns.
  • An email security solution is an effective “first line of defence” against so-called blended threats (emails containing an embedded URL).

Website traffic

Categorisation of web traffic was achieved by our Cloud Web Security solution.

Observation 1 – Legitimate web traffic

From mid-January (the start of this reporting period) through to the end of February a steady undercurrent of browsing requests to legitimate COVID or Coronavirus-themed URLs was apparent. These requests relate to so-called COVID-19 tracking sites (sites set up specifically to share data points related to the pandemic) and news websites. During the first two weeks of March 2020 a significant rise (5 million+ categorisations) was observed that may correlate with the onset of lockdown procedures enacted by global governments and a move to remote working.  A steady decline in activity was observed for the following three weeks, possibly relating to so-called “news fatigue” and gradual understanding of the “new normal.” Interest peaked again last week.

See Figure 1 below:

 

Observation 2 – Malicious web traffic

The chart below shows a steady increase in the number of COVID or Coronavirus-themed URLs categorized by Forcepoint as malicious from 9 March to the present date, with two spikes. As explained in the Highlights above cybercriminals have seen value in generating relevant looking, albeit nefarious, domains to encourage people to click on links in emails or generated by search.

See Figure 2 below:

 Web traffic to malicious COVID or Coronavirus-themed URLs (3-month period).

 

Observation 3 – Newly registered domains

Employees browsed to COVID or Coronavirus-themed domains that were Newly Registered only several hundred times per day for the duration of the three month period.  Such domains included so-called COVID trackers and newly registered news websites.

Spikes in browsing activity to such domains occurred at multiple times in March. One example of such a spike can be explained by interest in a legitimate Indian Covid-19 tracking site that correlated with an order prescribing lockdown in the country.

Note: In the figure below, we have not made a determination of whether the domain in question was malicious or legitimate.

See Figure 3 below:

 

Email traffic

Emails identified as “clean,” “virus” or “spam” were identified as such by our Cloud Email Security solution. During peak volumes, we identified 1.5 million total COVID-related emails per day. This is the disposition our customers will see in the product’s dashboard.

Observation 4 – legitimate email traffic

Employees at organisations around the globe have been sharing, and are in receipt of, legitimate emails containing COVID or Coronavirus-themed embedded URLs. Interest in such content began to noticeably rise in mid-March hitting one million legitimate emails per day across our systems. Interest remains phenomenally high since that point in time.

See Figure 4 below:

 

Observation 5 – spam emails

Spam emails containing COVID or Coronavirus-themed embedded URLs during January and February 2020 were observed in the tens of thousands per day. Scammers ramped up activity in mid-March as they made adjustments to existing spambots.  Over half a million scams per day were blocked by Forcepoint X-Labs from mid-March onwards. Notice the decline in such sends during the Easter and Passover period.

See Figure 5 below:

 

Observation 6 – malicious email traffic

Traditionally, the number of malicious emails seen per day through Forcepoint Cloud Email Security solutions are orders of magnitude less than the number of observed spam emails. The same can be said of COVID and Coronavirus-themed malicious emails. Up until the week of 16 March the number of malicious emails containing embedded COVID and Coronavirus-themed URLs had not increased for the previous eight weeks. The week of 23 March saw the largest increase (358%) of such emails compared with the final working day of the previous week. The first week of April saw a significant decline but the number of malicious emails has increased ever since.

See Figure 6 below:

 

What other active mitigation methods are being by deployed Forcepoint X-Labs?

  • Forcepoint X-Labs consumes third-party feeds that cover new malware. We are adopting our usual approaches to validate and ingest those feeds as we see an uptick in COVID-specific malware now included in those feeds.
  • We are subscribed to the COVID19 Cyber Threat Coalition. This feed has recently been set up by the security industry to share threat telemetry across the community. Read more about that initiative here: https://www.cyberthreatcoalition.org/
  • We are working closely with our customers to increase coverage and understand novel ways that malware authors are operating with COVID and Coronavirus-themed attacks.
  • Forcepoint X-Labs operates a 24/7 team that monitors our detection and adds new detection rules as appropriate.
  • Indicators and trends gained from one product are used to enhance protection across the range of Forcepoint products, including behavioral analytics.

Conclusion

Cybercriminals have adapted to exploit the public’s interest in COVID-19 and Coronavirus. This should not come as a surprise to defenders of global organisations as we see this modus operandi on a daily basis.  The email and web attack vectors remain key components in a cybercriminal’s arsenal.

In response to global events we have also seen changes in the behavior of employees within organisations around the world as they respond to mandates set by government or their own employers.

Carl Leonard

Principal Security Analyst

Carl Leonard is a Principal Security Analyst within Forcepoint X-Labs. He is responsible for enhancing threat protection and threat monitoring technologies at Forcepoint, in collaboration with the company’s global Labs teams. Focusing on protecting companies against the latest cyberattacks that...

Read more articles by Carl Leonard

Stuart Taylor

Sr. Director, Security Labs

Stuart Taylor is the Senior Director of Forcepoint X-Labs and is based in the UK.  Stuart has over 20 years of experience in the cybersecurity industry.  Prior to joining Forcepoint he spent several years running the Global Engineering Operations and UK Threat Lab of...

Read more articles by Stuart Taylor

À propos de Forcepoint

Forcepoint est une entreprise leader en cybersécurité pour la protection des utilisateurs et des données. Son objectif est de protéger les entreprises tout en stimulant la transformation et la croissance numériques. Nos solutions s’adaptent en temps réel à la façon dont les personnes interagissent avec les données, et offrent un accès sécurisé tout en permettant aux employés de créer de la valeur.