Researchers at Avanan warn that attackers are exploiting the collaboration and note-taking app Milanote to host phishing links.
“Major companies, including Uber, Chanel, Facebook, Google, and Nike, among many others, use [Milanote] in their daily work,” the researchers write. “Hackers have noticed, which is why Avanan analysts have noticed a dramatic increase in attacks utilizing files hosted on Milanote. Of the 1,430 most recent emails where Milanote is used, 1,367, or a staggering 95.5%, of them have been phishing.”
The attackers are sending emails with PDF attachments disguised as invoices. These files contain a link to a Milanote page, which in turn has a link to the actual phishing page. This helps the phishing emails to slip past security filters, since the emails themselves don’t contain malicious links or attachments.
“Other services use static scanners to scan attachments or links for malicious payloads,” the researchers write. “In response, hackers are bypassing those detection mechanisms by nesting the payloads in deeper layers within legitimate services, fooling the static scanners. This is part of a larger trend of hackers utilizing legitimate services to host malicious content. Because the scanner doesn’t go that deep, hackers can leverage these services to host their content and easily send it to users.”
Avanan notes that this isn’t unique to Milanote. Attackers can abuse many legitimate services to bypass security filters.
“Phishing content doesn’t just lie in email,” the researchers conclude. “It can be anywhere, hosted in apps that companies use on a daily basis. A holistic security solution cannot ignore these apps. Where there are lapses in security, hackers will find them. That’s the case with Milanote, and it’s easy to imagine this attack method reaching other popular cloud-based collaboration apps, potentially causing major damages to companies of all sizes and industries.”
Avanan has the story.