Threat actors seized the opportunities provided by the pandemic and conducted many phishing campaigns using COVID-19 themed lures. These campaigns took advantage of global interest in the novel coronavirus and preyed on fears of contracting COVID-19 to get people to open the emails, click on malicious hyperlinks, or open attachments that downloaded malware and ransomware payloads. Now that a large percentage of the population has been vaccinated, employers are opening up their offices again and employees are returning to the workplace.

The return to offices has presented another opportunity for scammers, who have launched a new phishing campaign targeting workers returning to offices. The emails appear to be a message from the CIO welcoming employees back to the workplace and claims to provide information about post-pandemic protocols and the procedures that have been put in place to accommodate returning workers to reduce the risk of infection.

The emails have been crafted to make them appear as if they have been sent internally, and include the logo of the targeted company and are signed by the CIO. The emails include a hyperlink that directs employees to a fake Microsoft SharePoint page that hosts two documents, both of which have the company’s branding. The documents are a COVID-19 factsheet and an implementation letter that includes steps that the company has taken based on updates provided by the Centers for Disease Control and Prevention (CDC), World Health Organization (WHO), and local health officials.

Most phishing campaigns would simply direct people to a landing page that hosts a phishing form where they are asked to enter their Office 365 credentials. This campaign is more sophisticated and includes an additional step. Nothing happens when an employee lands on the page. They are first required to click to open a document before the phish is activated. When the document is clicked, a fake Microsoft login prompt appears and credentials must then be entered in order to view the documents.

If credentials are entered, a message is then generated advising the employee that their account or password is not correct, and they are made to reenter their credentials several times before they are finally redirected to a genuine Microsoft page and are given access to the documents on OneDrive, most likely unaware that their credentials have been phished.

This COVID-19 phishing scam, like many others conducted throughout the pandemic, has a plausible lure. In this case, the emails have been well written and have been targeted for specific companies, making them very believable and likely to fool a great many employees. It is unclear what aims the attackers have once credentials have been harvested. They could be used to plunder sensitive information in Office 365 email accounts, would give the attackers a foothold in the corporate network for a more extensive compromise, or they could be sold to other threat groups such as ransomware gangs.

The best way to counter the threat is to prevent the malicious emails from arriving in inboxes, which requires an advanced spam filtering solution such as SpamTitan. With SpamTitan in place, phishing threats such as this will be identified and blocked at the gateway to ensure that employees’ phishing email identification skills are not put to the test.

If you want to improve your security posture and block more phishing threats, give the TitanHQ team a call today to discover how SpamTitan Email Security and the WebTitan DNS Filter can improve cybersecurity in your organization.