The relentless evolution of cyber threats has given rise to increasingly sophisticated tactics by attackers. A recent Microsoft phishing campaign stands out as a fresh example, leveraging advanced obfuscation techniques and AI assisted tools to evade traditional detection systems and target unsuspecting users. This blog delves into the intricacies of this campaign, revealing how it operates and how cutting-edge solutions like StrongestLayer’s Recursive-Predictive AI Detection Model (Zero-Day Detection Engine) are countering these threats.
The Anatomy of the Attack
When the attack url is opened, the victim lands on a classical Microsoft phishing sign in page that is hidden behind a captcha check to bypass crawlers.
1. Random Filler Text Surrounding the Functional Script
One hallmark of this phishing campaign is the use of completely random filler text that surrounds the actual malicious script. These nonsensical text spans act as camouflage, misleading both automated scanners and manual analysts by creating a noisy, chaotic environment.
For example, the script might include irrelevant comments or spans like the following:
<!-- <!-- <span>Incididunt turducken capicola andouille. Sausage anim officia, enim irure beef ribs occaecat id kielbasa corned beef. Occaecat jowl in esse tri-tip hamburger. Incididunt minim pastrami officia, fatback tri-tip cupidatat laboris. Aliquip consequat jerky mollit ea voluptate. Shank filet mignon t-bone cupidatat corned beef quis. Chuck eiusmod nulla venison excepteur jowl doner tri-tip ex anim nostrud ut. Nostrud laborum elit pig chuck, eu incididunt corned beef occaecat sunt culpa. Proident hamburger short ribs boudin id. Nostrud filet mignon turkey, adipisicing do aliqua ullamco jowl minim rump. Corned beef tempor duis commodo meatloaf ham hock ground round beef ribs. Drumstick frankfurter salami eu pastrami. Nulla duis hamburger capicola, occaecat pig ham hock tenderloin corned beef strip steak shoulder shank turkey. Cupidatat dolore sed tri-tip shoulder voluptate ut. Alcatra leberkas pariatur sirloin ut ball tip deserunt swine ut laboris kielbasa strip steak frankfurter.</span> -->
<script>
function MoPut3I(){}var GgJvjRN=Object['defineProperty'],wkJYZW,nB16ER,oahSi9t,Z__T3N3,oDqy9G,...
</script>
<span>Nostrud laborum elit pig chuck, eu incididunt corned beef occaecat sunt culpa...</span>
These meaningless snippets do not contribute to the functionality of the script but serve as a distraction, making it harder for analysts to focus on the malicious payload embedded within.
2. Highly Obfuscated Functional Script
Even the actual malicious script is rendered nearly indecipherable through machine-level obfuscation. Variable names are random, logical flow is convoluted, and functions are masked with unnecessary complexity to obscure their true intent. Here’s an example:
function MoPut3I(){}
var GgJvjRN = Object['defineProperty'], wkJYZW, nB16ER, oahSi9t, Z__T3N3;
function OKuGMD(MoPut3I){
return wkJYZW[MoPut3I < 0x3e ? MoPut3I + 0x7 : MoPut3I - 0x47];
}
wkJYZW = aTdOagO();
This obfuscation ensures that the malicious code operates as intended but is incomprehensible to analysts. Moreover, these scripts often include dynamic elements that adapt to their execution environment, further complicating detection.
Why Traditional Detection Methods Fail
Traditional signature-based detection systems are ill-equipped to counteract such sophisticated attacks due to the following reasons:
- Dynamic Obfuscation: Every iteration of the malicious code appears unique, rendering static signature rules ineffective.
- Camouflage Through Noise: The inclusion of random filler text distracts from identifying malicious patterns.
- Behavioral Masking: The scripts often execute malicious actions only in specific scenarios, avoiding detection during static analysis.
How StrongestLayer’s Zero Day Detection Engine Counteracts These Threats
StrongestLayer’s Zero Day Detection Engine offers a modern solution to these challenges by leveraging it’s advanced Recursive-Predictive AI detection model that is coupled with advanced dynamic behavioral analyses pathways. The incredible module called “The Time Machine” is a Recursive-Predictive AI Detection Model that feeds the Zero-Day detection engine with critical data that it builds from:
- Observing malicious redirection infrastructure over a prolonged period of time
- StrongestLayer’s advanced AI driven intent clustering algorithms that highlight hidden threat actors from the malicious data
- StrongestLayer’s advanced dynamic analysis algorithms that selectively stalk phishing sites for up to multiple days to detect behavioral anomalies via multiple analyses pathways.
Using this data, not only did StrongestLayer detect this threat, but we also detected the entire campaign that is still flying under the detection world’s radar with no major cybersecurity vendor marking any of these domains as malicious.
Final Thoughts
This Microsoft phishing campaign underscores the sophistication of modern cyber threats and the growing inadequacy of traditional detection methods. Attackers are now employing cutting-edge techniques, including the use of AI-based obfuscation tools to transform malicious code into an unreadable, cryptic format.
These tools leverage machine learning to dynamically generate complex, variable-heavy scripts that thwart human analysis and bypass signature-based detection systems. Additionally, random filler text and layered machine-level obfuscation add further complexity, creating a nearly impenetrable veil around the malicious payload.
However, solutions like StrongestLayer provide a robust defense against these advanced tactics by focusing on advanced AI driven detection algorithms that are coupled with advanced phishing threat intelligence platform that is purposefully built from scratch around phishing detection, and intent rather than relying solely on legacy detection means.
By employing dynamic behavioral analysis, AI-driven pattern recognition, and sophisticated infrastructure identification capabilities, StrongestLayer can unravel even the most intricately disguised threats.
In a world where phishing campaigns are evolving rapidly with the help of AI, adopting advanced detection technologies is essential to staying ahead of cybercriminals for any organization that wants to take their cyber defense capabilities to the next level.