Vendor Impersonated in Invoice Fraud Attack

May 20, 2020

Vendor email compromise, in which a compromised vendor sends invoice or payment attacks to their customers, is growing in popularity. An easier to detect method of this attack happens when a vendor is impersonated, rather than compromised. In this attack, the threat actor is impersonating a known vendor in order to receive payment for a fraudulent invoice.

Summary of Attack Target

  • Platform: Office 365
  • Email Security Bypassed: Proofpoint
  • Victims: Employees
  • Payload: Malicious Link
  • Technique: Impersonation

Overview of the Vendor Impersonation Attack

This organization communicates often with a known vendor. Recently, an employee from the accounting department received a message from what appeared to be the Assistant Controller / HR Administrator for this vendor. In the message, they were notified of an overdue invoice. In actuality, however, the attacker had registered a domain similar to that of the real vendor but changed the name slightly—for example, the real vendor might have been at, but the attacker registered, omitting the s in the domain.

The email states that there is an unpaid invoice, which must be paid to an updated bank account. The attacker alleges that their financial institution has changed as a result of the current pandemic and the suspicious sender then states they will send over the updated bank information once the recipient replies.

Should the recipient have fallen victim to this attack and made the payment, the organization would have had a significant financial loss and potentially opened itself up to more fraudulent exchanges in the future from the same attacker.

Why the Vendor Impersonation Attack is Effective

This attack leverages the COVID-19 pandemic as an excuse for the fraudulent payment update. The attacker injects urgency into the message by claiming there is an issue of a late unpaid invoice. The attack also impersonates a high-level employee and targets payroll and accounting employees who, because they expect legitimate invoices, may be less likely to scrutinize the sender information and attached invoices.

In addition, the attacker's email came from a domain that looked like the domain of the real company. The email domain the message was sent from was recently registered by the attackers with a slight difference. Further, the registrant information was not consistent with the real vendor, though anyone receiving the email would have had to spend a good deal of time digging into this information to discover it.

As an added element, the invoice attached to the email looked like a real invoice from the legitimate vendor, including their logo, their real address, and other real information.

Abnormal detected this fraudulent email due to to the unusual sender address and the suspicious financial request. Because the recipient had never interacted with this person, it was unusual for them to receive a financial request. Combined with the urgency of the email and the mention of the pandemic, it is clear that this email is malicious and Abnormal blocks it before it reaches inboxes.

To see how Abnormal can protect you from fraud in your supply chain, see a platform demo today.

Related Posts

Blog customer communications leads to product innovation
Learn how customers have influenced the latest round of product enhancements to better protect your organization from email-borne threats.
Read More
Blog attack detection efficacy cover
Abnormal’s relentless pursuit of innovation significantly improves the detection efficacy of hidden payloads in emails by an additional 5%.
Read More
Blog mnru cover
Estimating both the time and cost to complete a task has been a continual challenge for engineering teams as long as I’ve been working in industry. Coordinating the complex interactions and execution task sequencing across multiple tasks and people is a complex, ever-evolving challenge, and one that most teams struggle with daily.
Read More
Blog what do phishing emails cover
Phishing attacks are on the rise; the FBI reports that such attacks cost $54 billion in 2020, and phishing complaints increased by a whopping 110% from 2019 to 2020. If you're one of the many people targeted by a phishing email, you're not alone.
Read More
Blog holiday scams cover
We've arrived at that time of year—a time for reflection and celebration and spending time with family, and also that time of year where the cyber grinches hope to spoil the holiday fun.
Read More
Log4j email blog cover
Over the last few days, Abnormal has successfully blocked multiple attempts by attackers to deliver emails similar to these to our customers’ unsuspecting end users.
Read More
Blog securitry privacy cover
Customers place tremendous trust in Abnormal to protect them from the full spectrum of attacks when they provide us access to the email stored in Microsoft 365 or Google Workspace. To that end, we’re focused on protecting your data and building your trust.
Read More
Blog podcast role cto
Tim Tully, Partner at Menlo Ventures, grew up in Silicon Valley, where a love for coding was kindled in him. Tim is a technologist to the core, which innately led him to become an elite technical leader at companies like Splunk and Yahoo.
Read More
Blog canadian visa cover
Abnormal Security recently identified a scam aimed at the Canadian electronic travel authorization (eTA) program, which bears a striking resemblance to a long-standing fraud scheme described in our post from several weeks ago targeting TSA travel program applicants.
Read More
Automate abuse mailbox cover
Managing and monitoring an Abuse Mailbox can be a significant pain point for IT security teams, particularly large organizations with thousands of employees.
Read More
Blog calendar invite attack cover
Meeting invites are one of the most common types of emails sent today, so it should come as no surprise that attackers have found a way to manipulate them. Scores of recipients that utilize Abnormal Security recently received emails that contained a .ics attachment—an invitation file commonly used to populate online calendar applications with meeting and event information.
Read More
Blog saving memory python cover
At a hyper-growth startup, a solution from six months ago will unfortunately no longer scale. The business is growing rapidly, and this traffic to this service in particular was growing at an unprecedented rate. We hit a point where it needed re-architecting to support 10x the current scale.
Read More