Catching the big fish: Analyzing a large-scale phishing-as-a-service operation
In researching phishing attacks, we came across a campaign that used a rather high volume of newly created and unique subdomains—over 300,000 in a single run. This investigation led us down a rabbit hole as we unearthed one of the ... continue reading
Widespread credential phishing campaign abuses open redirector links
Microsoft has been actively tracking a widespread credential phishing campaign using open redirector links. Attackers combine these links with social engineering baits that impersonate well-known productivity tools and services to lure users into clicking. Doing so leads to a series ... continue reading
Trend-spotting email techniques: How modern phishing emails hide in plain sight
With the massive volume of emails sent each day, coupled with the many methods that attackers use to blend in, identifying the unusual and malicious is more challenging than ever. An obscure Unicode character in a few emails is innocuous ... continue reading
Innovate securely with Azure
This blog post has been co-authored by Carissa Broadbent, Product Marketing Manager, Security Marketing. Security is based on the inherent need for safety. Today, we see that need challenged more than ever. In the past year alone, we’ve witnessed an ... continue reading
Attackers use Morse code, other encryption methods in evasive phishing campaign
Cybercriminals attempt to change tactics as fast as security and protection technologies do. During our year-long investigation of a targeted, invoice-themed XLS.HTML phishing campaign, attackers changed obfuscation and encryption mechanisms every 37 days on average, demonstrating high motivation and skill ... continue reading
7 ways to harden your environment against compromise
Here at the global Microsoft Compromise Recovery Security Practice (CRSP), we work with customers who have experienced disruptive security incidents to restore trust in identity systems and remove adversary control. During 2020, the team responded to many incidents involving ransomware ... continue reading
Spotting brand impersonation with Swin transformers and Siamese neural networks
Every day, Microsoft Defender for Office 365 encounters around one billion brand impersonation emails. Our security solutions use multiple detection and prevention techniques to help users avoid divulging sensitive information to phishers as attackers continue refining their impersonation tricks. In ... continue reading
When coin miners evolve, Part 2: Hunting down LemonDuck and LemonCat attacks
[Note: In this two-part blog series, we expose a modern malware infrastructure and provide guidance for protecting against the wide range of threats it enables. Part 1 covered the evolution of the threat, how it spreads, and how it impacts ... continue reading
When coin miners evolve, Part 1: Exposing LemonDuck and LemonCat, modern mining malware infrastructure
[Note: In this two-part blog series, we expose a modern malware infrastructure and provide guidance for protecting against the wide range of threats it enables. Part 1 covers the evolution of the threat, how it spreads, and how it impacts ... continue reading
Behind the scenes of business email compromise: Using cross-domain threat data to disrupt a large BEC campaign
Microsoft 365 Defender researchers recently uncovered and disrupted a large-scale business email compromise (BEC) infrastructure hosted in multiple web services. Attackers used this cloud-based infrastructure to compromise mailboxes via phishing and add forwarding rules, enabling these attackers to get access ... continue reading
