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April 29, 2020

How Email Attackers Are Buying Domain Names to Get Inboxes

Explore how mass domain purchasing allows cyber-criminals to stay ahead of legacy email tools — and how cyber AI stops the threats that slip through.
Inside the SOC
Darktrace cyber analysts are world-class experts in threat intelligence, threat hunting and incident response, and provide 24/7 SOC support to thousands of Darktrace customers around the globe. Inside the SOC is exclusively authored by these experts, providing analysis of cyber incidents and threat trends, based on real-world experience in the field.
Written by
Dan Fein
VP, Product
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29
Apr 2020

It is by now common knowledge that the vast majority of cyber-threats start with an email. In the current working conditions, this is more true than ever – with a recent study reporting a 30,000% increase in phishing, websites, and malware targeting remote users.

Many email security tools struggle to detect threats they encounter for the first time. Attackers know this and are leveraging many techniques to take advantage of this fundamental flaw. This includes automation to mutate common threat variants, resulting in a massive increase in unknown threats. Another technique, which will be the focus of this blog post, is the rapid and widespread creation of new domains in order to evade reputation checks and signature-based detection.

The recent surge in domain creation

While traditional tools have to rely on identifying campaigns and patterns across multiple emails to establish whether or not an email is malicious, Cyber AI technology doesn’t require classifying emails into buckets in order to know they don’t belong. There is no need, therefore, to actively track campaigns. But as security researchers, it’s hard to miss some trends.

Since the coronavirus outbreak, we have seen the number of domains registered related to COVID-19 increase by 130,000. In this time, 60% of all spear phishing threats neutralized by Antigena Email were related to COVID-19 or remote work. Another recent study determined that 10,000 coronavirus-related domains are created every day, with roughly nine out of ten of these either malicious or attempting to generate sales of fake products.

With attackers also taking advantage of changing online behaviors arising from the pandemic, another trend we’ve seen is the proliferation of the keyword ‘Zoom’ in some of the unpopular domains that bypassed traditional tools, as attackers leverage the video conferencing platform’s recent rise in usage.

“I believe that hackers identified coronavirus as something users are desperate to find information on. Panic leads to irrational thinking and people forget the basics of cyber security.”

— COO, Atlas VPN

I recently wrote a blog post on the idea of ‘fearware’ and why it’s so successful. Right now, people are desperate for information, and attackers know this. Cyber-criminals play into fear, uncertainty, and doubt (FUD) through a number of mechanisms, and we have since seen a variety of imaginative attempts to engage recipients. These emails range from fake ‘virus trackers’, to sending emails purporting to be from Amazon, claiming an unmanageable rise in newly registered accounts, and demanding “re-registration” of the recipient’s credit card details should they wish to keep their account.

Domain name purchasing: A vicious cycle

Purchasing thousands of new domains and sending malicious emails en masse is a tried and tested technique that cyber-criminals have been leveraging for decades. Now with automation, they’re doing it faster than ever before.

Here’s why it works.

Traditional security tools work by analyzing emails in isolation, measuring them against static blacklists of ‘known bads’. By way of analogy, the gateway tool here is acting like a security guard standing at the perimeter of an organization’s physical premises, asking every individual who enters: “are you malicious?”

The binary answer to this sole question is extracted by looking at some metadata around the email, including the sender’s IP, their email address domain, and any embedded links or attachments. They analyze this data in a vacuum, and at face value, with no consideration towards the relationship between that data, the recipient, and the rest of the business. They run reputation checks, asking “have I seen this IP or domain before?” Crucially, if the answer is no, they let them straight through.

To spell that out, if the domain is brand new, it won’t have a reputation, and as these traditional tools have a limited ability to identify potential harmful elements via any other means, they have no choice but to let them in by default.

These methods barely scratch the surface of a much wider range of characteristics that a malicious email might contain. And as email threats get ever more sophisticated, the ‘innocent until proven guilty approach’ is not enough. For a comprehensive check, we would want to ask: does the domain have any previous relationship with the recipient? The organization as a whole? Does it look suspiciously visually similar to other domains? Is this the first time we’ve seen an inbound email from this user? Has anybody in the organization ever shared a link with this domain? Has any user ever visited this link?

Legacy tools are blatantly asking the wrong questions, to which attackers know the answers. And usually, they can skirt by these inattentive security guards by paying just a few pennies for new domains.

How to buy your way in

Let’s look at the situation from an attacker’s perspective. They just need one email to land and it could be keys to the kingdom, so an upfront purchase of a few thousand new domains will almost inevitably pay off. And they’d pay the price as long as it’s working and they’re profiting.

This is exactly what attackers are doing. Newly-registered domains consistently get through gateways until these traditional tools are armed with enough information to determine that the domains are bad, by which point thousands or even millions of emails could have been successfully delivered. As soon as the attack infrastructure is worn out, the attackers will abandon it, and very easily just purchase and deploy a new set of domains.

And so, the vicious cycle continues. Like a game of ‘whack-a-mole’, these legacy ‘solutions’ will continue to hammer down on recognized ‘bad’ emails – all the while more malicious domains are being created in the thousands in preparation for the next campaign. This is the ‘Domain Game’, and it’s a hard game for defenders to win.

Asking the right questions

Thankfully, the solution to this problem is as simple as the problem itself. It requires a movement away from the legacy approach and towards deploying technology that is up to par with the speed and scale of today’s attackers.

In the last two years, new technologies have emerged that leverage AI, seeking to understand the human behind the email address. Rather than inspecting incoming traffic at the surface-level and asking binary questions, this paradigm shift away from this insufficient legacy approach asks the right questions: not simply “are you malicious?”, but crucially: “do you belong?”

Informed by a nuanced understanding of the recipient, their peers, and the organization at large, every inbound, outbound, and internal email is analyzed in context, and is then re-analyzed over and over again in light of evolving evidence. Asking the right questions and understanding the human invariably sets a far higher standard for acceptable catch rates with unknown threats on first encounter. This approach far outpaces traditional email defenses which have proven to fail and leave companies and their employees vulnerable to malicious emails sitting in their inboxes.

Rather than desperately bashing away at blacklisted domains and IP addresses in an ill-fated attempt to beat the attackers, we can change the game altogether, tilting the scales in favor of the defenders – securing our inboxes and our organizations at large.

Learn more about Antigena Email.

Inside the SOC
Darktrace cyber analysts are world-class experts in threat intelligence, threat hunting and incident response, and provide 24/7 SOC support to thousands of Darktrace customers around the globe. Inside the SOC is exclusively authored by these experts, providing analysis of cyber incidents and threat trends, based on real-world experience in the field.
Written by
Dan Fein
VP, Product

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July 3, 2025

Top Eight Threats to SaaS Security and How to Combat Them

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The latest on the identity security landscape

Following the mass adoption of remote and hybrid working patterns, more critical data than ever resides in cloud applications – from Salesforce and Google Workspace, to Box, Dropbox, and Microsoft 365.

On average, a single organization uses 130 different Software-as-a-Service (SaaS) applications, and 45% of organizations reported experiencing a cybersecurity incident through a SaaS application in the last year.

As SaaS applications look set to remain an integral part of the digital estate, organizations are being forced to rethink how they protect their users and data in this area.

What is SaaS security?

SaaS security is the protection of cloud applications. It includes securing the apps themselves as well as the user identities that engage with them.

Below are the top eight threats that target SaaS security and user identities.

1.  Account Takeover (ATO)

Attackers gain unauthorized access to a user’s SaaS or cloud account by stealing credentials through phishing, brute-force attacks, or credential stuffing. Once inside, they can exfiltrate data, send malicious emails, or escalate privileges to maintain persistent access.

2. Privilege escalation

Cybercriminals exploit misconfigurations, weak access controls, or vulnerabilities to increase their access privileges within a SaaS or cloud environment. Gaining admin or superuser rights allows attackers to disable security settings, create new accounts, or move laterally across the organization.

3. Lateral movement

Once inside a network or SaaS platform, attackers move between accounts, applications, and cloud workloads to expand their foot- hold. Compromised OAuth tokens, session hijacking, or exploited API connections can enable adversaries to escalate access and exfiltrate sensitive data.

4. Multi-Factor Authentication (MFA) bypass and session hijacking

Threat actors bypass MFA through SIM swapping, push bombing, or exploiting session cookies. By stealing an active authentication session, they can access SaaS environments without needing the original credentials or MFA approval.

5. OAuth token abuse

Attackers exploit OAuth authentication mechanisms by stealing or abusing tokens that grant persistent access to SaaS applications. This allows them to maintain access even if the original user resets their password, making detection and mitigation difficult.

6. Insider threats

Malicious or negligent insiders misuse their legitimate access to SaaS applications or cloud platforms to leak data, alter configurations, or assist external attackers. Over-provisioned accounts and poor access control policies make it easier for insiders to exploit SaaS environments.

7. Application Programming Interface (API)-based attacks

SaaS applications rely on APIs for integration and automation, but attackers exploit insecure endpoints, excessive permissions, and unmonitored API calls to gain unauthorized access. API abuse can lead to data exfiltration, privilege escalation, and service disruption.

8. Business Email Compromise (BEC) via SaaS

Adversaries compromise SaaS-based email platforms (e.g., Microsoft 365 and Google Workspace) to send phishing emails, conduct invoice fraud, or steal sensitive communications. BEC attacks often involve financial fraud or data theft by impersonating executives or suppliers.

BEC heavily uses social engineering techniques, tailoring messages for a specific audience and context. And with the growing use of generative AI by threat actors, BEC is becoming even harder to detect. By adding ingenuity and machine speed, generative AI tools give threat actors the ability to create more personalized, targeted, and convincing attacks at scale.

Protecting against these SaaS threats

Traditionally, security leaders relied on tools that were focused on the attack, reliant on threat intelligence, and confined to a single area of the digital estate.

However, these tools have limitations, and often prove inadequate for contemporary situations, environments, and threats. For example, they may lack advanced threat detection, have limited visibility and scope, and struggle to integrate with other tools and infrastructure, especially cloud platforms.

AI-powered SaaS security stays ahead of the threat landscape

New, more effective approaches involve AI-powered defense solutions that understand the digital business, reveal subtle deviations that indicate cyber-threats, and action autonomous, targeted responses.

[related-resource]

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About the author
Carlos Gray
Senior Product Marketing Manager, Email

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July 2, 2025

Pre-CVE Threat Detection: 10 Examples Identifying Malicious Activity Prior to Public Disclosure of a Vulnerability

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Vulnerabilities are weaknesses in a system that can be exploited by malicious actors to gain unauthorized access or to disrupt normal operations. Common Vulnerabilities and Exposures (or CVEs) are a list of publicly disclosed cybersecurity vulnerabilities that can be tracked and mitigated by the security community.

When a vulnerability is discovered, the standard practice is to report it to the vendor or the responsible organization, allowing them to develop and distribute a patch or fix before the details are made public. This is known as responsible disclosure.

With a record-breaking 40,000 CVEs reported for 2024 and a predicted higher number for 2025 by the Forum for Incident Response and Security Teams (FIRST) [1], anomaly-detection is essential for identifying these potential risks. The gap between exploitation of a zero-day and disclosure of the vulnerability can sometimes be considerable, and retroactively attempting to identify successful exploitation on your network can be challenging, particularly if taking a signature-based approach.

Detecting threats without relying on CVE disclosure

Abnormal behaviors in networks or systems, such as unusual login patterns or data transfers, can indicate attempted cyber-attacks, insider threats, or compromised systems. Since Darktrace does not rely on rules or signatures, it can detect malicious activity that is anomalous even without full context of the specific device or asset in question.

For example, during the Fortinet exploitation late last year, the Darktrace Threat Research team were investigating a different Fortinet vulnerability, namely CVE 2024-23113, for exploitation when Mandiant released a security advisory around CVE 2024-47575, which aligned closely with Darktrace’s findings.

Retrospective analysis like this is used by Darktrace’s threat researchers to better understand detections across the threat landscape and to add additional context.

Below are ten examples from the past year where Darktrace detected malicious activity days or even weeks before a vulnerability was publicly disclosed.

ten examples from the past year where Darktrace detected malicious activity days or even weeks before a vulnerability was publicly disclosed.

Trends in pre-cve exploitation

Often, the disclosure of an exploited vulnerability can be off the back of an incident response investigation related to a compromise by an advanced threat actor using a zero-day. Once the vulnerability is registered and publicly disclosed as having been exploited, it can kick off a race between the attacker and defender: attack vs patch.

Nation-state actors, highly skilled with significant resources, are known to use a range of capabilities to achieve their target, including zero-day use. Often, pre-CVE activity is “low and slow”, last for months with high operational security. After CVE disclosure, the barriers to entry lower, allowing less skilled and less resourced attackers, like some ransomware gangs, to exploit the vulnerability and cause harm. This is why two distinct types of activity are often seen: pre and post disclosure of an exploited vulnerability.

Darktrace saw this consistent story line play out during several of the Fortinet and PAN OS threat actor campaigns highlighted above last year, where nation-state actors were seen exploiting vulnerabilities first, followed by ransomware gangs impacting organizations [2].

The same applies with the recent SAP Netweaver exploitations being tied to a China based threat actor earlier this spring with subsequent ransomware incidents being observed [3].

Autonomous Response

Anomaly-based detection offers the benefit of identifying malicious activity even before a CVE is disclosed; however, security teams still need to quickly contain and isolate the activity.

For example, during the Ivanti chaining exploitation in the early part of 2025, a customer had Darktrace’s Autonomous Response capability enabled on their network. As a result, Darktrace was able to contain the compromise and shut down any ongoing suspicious connectivity by blocking internal connections and enforcing a “pattern of life” on the affected device.

This pre-CVE detection and response by Darktrace occurred 11 days before any public disclosure, demonstrating the value of an anomaly-based approach.

In some cases, customers have even reported that Darktrace stopped malicious exploitation of devices several days before a public disclosure of a vulnerability.

For example, During the ConnectWise exploitation, a customer informed the team that Darktrace had detected malicious software being installed via remote access. Upon further investigation, four servers were found to be impacted, while Autonomous Response had blocked outbound connections and enforced patterns of life on impacted devices.

Conclusion

By continuously analyzing behavioral patterns, systems can spot unusual activities and patterns from users, systems, and networks to detect anomalies that could signify a security breach.

Through ongoing monitoring and learning from these behaviors, anomaly-based security systems can detect threats that traditional signature-based solutions might miss, while also providing detailed insights into threat tactics, techniques, and procedures (TTPs). This type of behavioral intelligence supports pre-CVE detection, allows for a more adaptive security posture, and enables systems to evolve with the ever-changing threat landscape.

Credit to Nathaniel Jones (VP, Security & AI Strategy, Field CISO), Emma Fougler (Global Threat Research Operations Lead), Ryan Traill (Analyst Content Lead)

References and further reading:

  1. https://www.first.org/blog/20250607-Vulnerability-Forecast-for-2025
  2. https://cloud.google.com/blog/topics/threat-intelligence/fortimanager-zero-day-exploitation-cve-2024-47575
  3. https://thehackernews.com/2025/05/china-linked-hackers-exploit-sap-and.html

Related Darktrace blogs:

*Self-reported by customer, confirmed afterwards.

**Updated January 2024 blog now reflects current findings

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