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 created and introduced to replace Brazil’s old and deprecated transfer methods TED and DOC. PIX’s new functionalities made it significantly cheaper and faster for transactions to be completed, allowing transfers to be conducted any time of the day, including weekends — functionality not available in […]

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. This means if victims don’t have backups of their files and databases, there may not be any way to recover the kidnapped data without paying the ransom. Continue reading Obfuscation Techniques in Ransomweb “Ransomware” at Sucuri Blog.

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 a website file. While this may not seem like a lot of code, this short string can be used to load PHP web shells on your website at the attacker’s whim —  while also preventing website visitors and administrators from detecting the malicious behavior. Continue […]

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 scans came up clean. Attackers are writing new pieces of malware like it’s going out of style, so there are very frequently new injections to track down and remove. Continue reading Bogus CSS Injection Leads to Stolen Credit Card Details at Sucuri Blog.

SEO Spam Links in Nulled Plugins

It’s not unusual to see website owners running things on a budget. Choosing a safe and reliable hosting company, buying a nice domain name, boosting posts on social media, and ranking on search engines — all this costs a lot of money. At the end of the day, some site owners may even choose to cut expenses by installing pirated (or nulled) software on their websites. Unfortunately, as discussed in some of our earlier posts about free software and fake verification, these “free” components may still come with a hefty price tag. Continue reading SEO Spam Links in Nulled Plugins […]

The Dangers of Using Abandoned Plugins & Themes

It’s not very often that we see abandoned components being used on a website — but when we do, it’s most often because the website was exhibiting malware-like behavior and we were called to investigate and clean up the site. Old and abandoned plugins and themes are a good target for opportunistic attackers who are looking for any expired domains that might be used by those components. Once an attacker gets a hold of those domains, they’re able to distribute malware to any users that still have that resource installed on their site. Continue reading The Dangers of Using Abandoned […]

Why You Should Monitor Your Website

In an effort to maintain unauthorized access or profit off a website’s environment long after an initial compromise, attackers commonly leverage a variety of different techniques and tactics. These techniques range from adding backdoors, stealing sensitive data, redirecting the site to other third-party resources, or even injecting specially crafted links to give their own sites a SERP boost. Knowing exactly which JavaScript files are supposed to load whenever you visit your website is a good practice — and in many cases, a great way to tell if your site has been compromised. Continue reading Why You Should Monitor Your Website […]

Malware Dropper Takes Advantage of COVID-19 Pandemic

Since April, our team has been tracking the spread of a PHP malware dropper. It’s impacting unsuspecting victims who thought they were downloading a mapping software to monitor the spread of the COVID-19 pandemic. While the attack is likely spread through a variety of vectors, we have verified that bad actors are using other compromised websites to serve the malicious payload to users. Malware Dropper Behavior To distribute their malicious executable, hackers create two subdirectories — comap and cvmap — inside a compromised WordPress wp-admin directory. Continue reading Malware Dropper Takes Advantage of COVID-19 Pandemic at Sucuri Blog.

Fake WordPress Functions Conceal assert() Backdoor

A few weeks ago, I was manually inspecting some files on a compromised website. While checking on a specific WooCommerce file, I noticed something interesting. Among 246 other lines, this very specific part stood out to me: $config = wp_dbase_config_init(‘_as_sert’); For those readers familiar with PHP functions commonly misused by hackers, you may have already spotted _as_sert as something suspicious. Since it resembles the assert() function, let’s check the PHP definition of the function: bool assert ( mixed $assertion [, string $description ] ) assert() will check the given assertion and take appropriate action if its result is FALSE. Continue […]

Obfuscation Techniques in MARIJUANA Shell “Bypass”

Attackers are always trying to come up with new ways to evade detection from the wide range of security controls available for web applications. This also extends to malware like PHP shells, which are typically left on compromised websites as a backdoor to maintain unauthorized access. MARIJUANA is the name of a PHP shell that we have been tracking since last year. The author has a GitHub page which promotes a claim that the shell possesses a “stealth” mode, which can be used to bypass website security services like web application firewalls (WAFs). Continue reading Obfuscation Techniques in MARIJUANA Shell […]