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

4/2/2020
06:35 PM
Connect Directly
Twitter
LinkedIn
RSS
E-Mail
50%
50%

Phishers Try 'Text Direction Deception' Technique to Bypass Email Filters

With COVID-19 concerns running high, attackers are trying new tactics to get to users.

Scammers can be pretty innovative when it comes to finding new ways to sneak phishing messages past secure email gateways and other filtering mechanisms.

One example is "text direction deception," a tactic where an attacker forces an HTML rendering engine to correctly display text that has been deliberately entered backward in the code — for example, getting text that exists in HTML code as "563 eciffO" to render forward correctly as "Office 365."

Security vendor Inky Technologies discovered the direction deception tactic being used in an email that was part of a phishing campaign. In a report this week, the company described the tactic as designed to trick security controls that filter email messages based on whether the emails contain text and text sequences that have been previously associated with phishing scams.

Such tactics could become more common as cybercriminals take advantage of the worldwide concern around the COVID-19 pandemic to fill email inboxes with phishing messages designed to trick users in various ways.

Just this week, for instance, Menlo Security reported what it described as a sophisticated, multistage phishing campaign targeted at stealing the credentials of specific individuals in the executive and finance teams at hundreds of companies.

The emails contained a phishing message that purported to be from the CEOs of each of the targeted companies. The emails also included an attachment that seemingly contained COVID-19 related employee information. The attachment contained a shortened link to a hosted form on a legitimate Microsoft service that prompted users for their login credentials.

With many email security products getting better at spotting scam emails, criminals have begun innovating as well. "To increase their success rate, attackers have adopted multi-stage attacks leveraging email, PDF attachments, and trusted SaaS services," Menlo said in its report. According to the security vendor, email users have been falling for such COVID-19 themed phishing emails in much larger numbers than with other phishing scams.

The rush to take advantage of COVID-19 fears is so high that some are dusting off old phishing kits and redeploying them again with a pandemic-themed lure. According to Akamai, its researchers have observed several threat actors recycling old phishing kits in new COVID-19 campaigns.

Innovative Tactics
Dave Baggett, CEO and co-founder of Inky, says he expects more criminals to use innovative tactics, such as text direction deception and other similar gambits, in COVID-19 related scams. As one example of another tactic, he points to COVID-19 scams where text in the HTML has the font size set to zero so it's effectively invisible to secure email gateways.

"This is just another method the attacker can use to hide text," he says of the text direction reversal method. "Anecdotally, it's used a lot less frequently than ordinary zero font, but that's probably because it will take a while for this tactic to find its way into phishing kits purveyed on the Dark Web."

Most secure email gateways use statistical models to learn the text sequences associated with legitimate email and that are associated with phishing, spam and other bad email, Inky said. "These models — the workhorse of mail protection since the 90s — learn, for example, that dollar signs in the subject line and 'make money fast!' in the body correlate with spam," the vendor said it its report.

Direction deception allows the attackers to thwart these pattern-matching capabilities by ensuring the text the email gateways are looking for doesn't appear in the HTML code. At the same time, the tactic ensures that email recipients see the text as perfectly normal, Inky said.

The security vendor described text direction deception as taking advantage of certain obscure capabilities in Cascading Style Sheets (CSS), a technology for describing how HTML documents are presented to the user. The capabilities pertain to how documents containing scripts like Arabic, which flows from the right to the left, and Latin are displayed. The specific property that the attackers abused allowed them to control how text is read and rendered, the vendor said.

Related Content:

Check out The Edge, Dark Reading's new section for features, threat data, and in-depth perspectives. Today's featured story: "Untangling Third-Party Risk (and Fourth, and Fifth...)."

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
 

Recommended Reading:

Comment  | 
Print  | 
More Insights
Comments
Newest First  |  Oldest First  |  Threaded View
COVID-19: Latest Security News & Commentary
Dark Reading Staff 10/23/2020
7 Tips for Choosing Security Metrics That Matter
Ericka Chickowski, Contributing Writer,  10/19/2020
Russian Military Officers Unmasked, Indicted for High-Profile Cyberattack Campaigns
Kelly Jackson Higgins, Executive Editor at Dark Reading,  10/19/2020
Register for Dark Reading Newsletters
White Papers
Video
Cartoon
Current Issue
Special Report: Computing's New Normal
This special report examines how IT security organizations have adapted to the "new normal" of computing and what the long-term effects will be. Read it and get a unique set of perspectives on issues ranging from new threats & vulnerabilities as a result of remote working to how enterprise security strategy will be affected long term.
Flash Poll
How IT Security Organizations are Attacking the Cybersecurity Problem
How IT Security Organizations are Attacking the Cybersecurity Problem
The COVID-19 pandemic turned the world -- and enterprise computing -- on end. Here's a look at how cybersecurity teams are retrenching their defense strategies, rebuilding their teams, and selecting new technologies to stop the oncoming rise of online attacks.
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2020-24847
PUBLISHED: 2020-10-23
A Cross-Site Request Forgery (CSRF) vulnerability is identified in FruityWifi through 2.4. Due to a lack of CSRF protection in page_config_adv.php, an unauthenticated attacker can lure the victim to visit his website by social engineering or another attack vector. Due to this issue, an unauthenticat...
CVE-2020-24848
PUBLISHED: 2020-10-23
FruityWifi through 2.4 has an unsafe Sudo configuration [(ALL : ALL) NOPASSWD: ALL]. This allows an attacker to perform a system-level (root) local privilege escalation, allowing an attacker to gain complete persistent access to the local system.
CVE-2020-5990
PUBLISHED: 2020-10-23
NVIDIA GeForce Experience, all versions prior to 3.20.5.70, contains a vulnerability in the ShadowPlay component which may lead to local privilege escalation, code execution, denial of service or information disclosure.
CVE-2020-25483
PUBLISHED: 2020-10-23
An arbitrary command execution vulnerability exists in the fopen() function of file writes of UCMS v1.4.8, where an attacker can gain access to the server.
CVE-2020-5977
PUBLISHED: 2020-10-23
NVIDIA GeForce Experience, all versions prior to 3.20.5.70, contains a vulnerability in NVIDIA Web Helper NodeJS Web Server in which an uncontrolled search path is used to load a node module, which may lead to code execution, denial of service, escalation of privileges, and information disclosure.