Two large phishing attacks, aimed at a combined 10,000 victims, spoofed emails from FedEx and DHL Express in an attempt to steal their targets' business email account credentials.
The attackers' techniques included social engineering, brand impersonation, and link redirects, report Armorblox researchers who detected the campaigns. They also hosted phishing pages on Quip and Google Firebase. Because these domains are considered reputable, malicious emails may bypass security filters configured to block bad links and files, researchers note.
Consider the attack flow for a fake FedEx message, which claimed to hold a scanned document for the victim to review. Clicking the link redirects the recipient to a file hosted on Quip, an add-on tool for Salesforce that offers things such as documents, spreadsheets, and slides. The page says the victim has FedEx files and prompts them to "Click Here to Review Document."
If clicked, the recipient is brought to a final phishing page that resembles the Microsoft login portal but is hosted on Google Firebase. Services such as Google Sites and Quip often have free versions and are easy to use, which lowers the bar for criminals who launch phishing attacks.
The second campaign sends emails that impersonate DHS Express and inform the recipients that a parcel has arrived for them. Victims are told their parcel couldn't be delivered due to incorrect delivery details and are prompted to download an attached file to verify the shipping information.
Downloading and opening this attachment previews a spreadsheet that seems to be shipping documents, but above that is a login prompt impersonating the Adobe brand. While it's possible attackers were seeking Adobe credentials, researchers believe it's more likely this also targeted business email credentials — the login box is prefilled with the recipient's work email address.
In both attacks, entering fake details on the fraudulent login page returns an error, requesting correct details. This could indicate a back-end tool to check the validity of entered details, or the attackers may be planning to collect as many details as they can, and an error message will appear regardless of whether it's correct.
Read the full Armorblox blog post for more details.