Dark Reading is part of the Informa Tech Division of Informa PLC

This site is operated by a business or businesses owned by Informa PLC and all copyright resides with them.Informa PLC's registered office is 5 Howick Place, London SW1P 1WG. Registered in England and Wales. Number 8860726.

Attacks/Breaches

6/25/2019
07:10 PM
Connect Directly
Twitter
LinkedIn
RSS
E-Mail
50%
50%

Email Threats Continue to Grow as Attackers Evolve, Innovate

Threat actors increasingly using malicious URLs, HTTPS domains, file-sharing sites in email attacks, FireEye says.

Email continues to be an extremely effective vector for delivering malicious content because of how adept attackers have become at tricking users over the years.

The latest examples include the increasing use of malicious URLs in emails rather than attachments, a trend toward use of HTTPS domains for hosting malicious sites, and new variants of impersonation fraud.

FireEye recently analyzed a sample set of 1.3 billion emails for the first three months of 2019 and counted more URL-based email attacks than attachment-based ones in the first quarter.

URL attacks involve emails with embedded links pointing to a malware download site or a phishing site designed to steal a user's account credentials or credit card data. Emails containing such links are often harder to detect and block than ones with malicious attachments, according to FireEye.

In many cases, attackers have been embedding such links in emails with very little or no content in them in an attempt to bypass email filters and to try and get the recipient curious enough to click on the link. According to FireEye, there was a spike in the number of content-less emails in January. Sometimes the emails have contained nonclickable URLs that are activated when a user copies and pastes it into a browser, the vendor noted.

FireEye observed a troubling 26% quarter-over-quarter increase in malicious URLs pointing to phishing sites hosted on HTTPS domains. The sites, and the phishing lures to get users there, often spoofed major brands. In fact, in Q1 2019, FireEye observed a 17% quarter-over-quarter increase in phishing attacks involving the misuse of a well-known brand name.

Microsoft was by far the most spoofed brand, accounting for 30% of all detections in the first quarter. Other frequently spoofed brands included Apple, Amazon, PayPal, and OneDrive.

"The increase in phishing sites using HTTPS was a very interesting shift," says Ken Bagnall, vice president of email security at FireEye. Also significant was the number of phishing sites spoofed to appear like different Microsoft login pages that FireEye observed in the first quarter. "This really highlights how useful attackers see getting access to a victim's Office 365 credentials," Bagnall says.

Exploiting Trust in File-Sharing Sites
Also increasing significantly in the first quarter was the number of URL links pointing to malicious files hosted on widely trusted cloud-hosted file sharing sites, such as Dropbox, OneDrive, Google Drive, and WeTransfer. Threat actors are increasingly using such file-sharing services to host malicious content because the sites pass the domain reputation checks that many security tools use for vetting links, FireEye said.

Some of these file-sharing sites even let users preview the hosted content and offer a link that can be clicked without having to download the file, the vendor said. "Attackers are simulating user behavior here," Bagnall notes. File-sharing sites have become very common, so users are likely to be less suspicious of interacting with content on these services. "There was a very significant increase in OneDrive this quarter, and we will see more targeting based on customers usage of cloud services in their workflow," he says.

Impersonation email attacks, where an attacker might pretend to be a CEO or a CFO to trick employees into initiating a fraudulent wire transfer or some other action, continued to grow and evolve in the first quarter. In the past, such attacks targeted employees in the accounts payable department. In this year's first quarter, FireEye observed an increase in attacks targeting the payroll and supply chain departments.

For organizations, such developments highlight the need for multilayered defenses. On the technology front, they need a tool stack that innovates in line with attacker behavior, Bagnall says. Security awareness training and education are important as well. So are controls that protect payments processes and prevent individuals in an organization to change bank details or initiate similar actions based on an email communication alone, he says.

Related Content:

 

Jai Vijayan is a seasoned technology reporter with over 20 years of experience in IT trade journalism. He was most recently a Senior Editor at Computerworld, where he covered information security and data privacy issues for the publication. Over the course of his 20-year ... View Full Bio

Comment  | 
Print  | 
More Insights
Comments
Newest First  |  Oldest First  |  Threaded View
I 'Hacked' My Accounts Using My Mobile Number: Here's What I Learned
Nicole Sette, Director in the Cyber Risk practice of Kroll, a division of Duff & Phelps,  11/19/2019
DevSecOps: The Answer to the Cloud Security Skills Gap
Lamont Orange, Chief Information Security Officer at Netskope,  11/15/2019
Attackers' Costs Increasing as Businesses Focus on Security
Robert Lemos, Contributing Writer,  11/15/2019
Register for Dark Reading Newsletters
White Papers
Video
Cartoon Contest
Current Issue
Navigating the Deluge of Security Data
In this Tech Digest, Dark Reading shares the experiences of some top security practitioners as they navigate volumes of security data. We examine some examples of how enterprises can cull this data to find the clues they need.
Flash Poll
Rethinking Enterprise Data Defense
Rethinking Enterprise Data Defense
Frustrated with recurring intrusions and breaches, cybersecurity professionals are questioning some of the industrys conventional wisdom. Heres a look at what theyre thinking about.
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2019-13157
PUBLISHED: 2019-11-22
nsGreen.dll in Naver Vaccine 2.1.4 allows remote attackers to overwrite arbitary files via directory traversal sequences in a filename within nsz archive.
CVE-2012-2079
PUBLISHED: 2019-11-22
A cross-site request forgery (CSRF) vulnerability in the Activity module 6.x-1.x for Drupal.
CVE-2019-11325
PUBLISHED: 2019-11-21
An issue was discovered in Symfony before 4.2.12 and 4.3.x before 4.3.8. The VarExport component incorrectly escapes strings, allowing some specially crafted ones to escalate to execution of arbitrary PHP code. This is related to symfony/var-exporter.
CVE-2019-18887
PUBLISHED: 2019-11-21
An issue was discovered in Symfony 2.8.0 through 2.8.50, 3.4.0 through 3.4.34, 4.2.0 through 4.2.11, and 4.3.0 through 4.3.7. The UriSigner was subject to timing attacks. This is related to symfony/http-kernel.
CVE-2019-18888
PUBLISHED: 2019-11-21
An issue was discovered in Symfony 2.8.0 through 2.8.50, 3.4.0 through 3.4.34, 4.2.0 through 4.2.11, and 4.3.0 through 4.3.7. If an application passes unvalidated user input as the file for which MIME type validation should occur, then arbitrary arguments are passed to the underlying file command. T...