MuddyWater Hijacks Microsoft Teams in False Flag Ransomware Attack

Emily Davis · 2026-05-06

You might think you're safe just because you're careful with email links. But attackers are getting smarter, and one Iranian state-sponsored group just proved that. MuddyWater, also known as Mango Sandstorm, Seedworm, and Static Kitten, has been linked to a ransomware attack that uses a pretty clever trick. It's what experts call a "false flag" operation, and it's designed to make you trust the wrong person. The attack was spotted by Rapid7 back in early 2026. Instead of the usual phishing email, these hackers are using Microsoft Teams to start the whole infection chain. Think about that for a second. You're sitting at your desk, a message pops up from someone who looks like a colleague, and you don't think twice. That's exactly what they're counting on. ### How the Attack Actually Works So here's how it goes down. The hackers send a message through Microsoft Teams pretending to be from someone you know. They might claim there's an urgent issue with a shared document or a security update that needs your attention. The message includes a link that looks legit, but it's not. Once you click, you're taken to a fake login page that steals your credentials. But it doesn't stop there. After they have your login info, they use it to move deeper into your network. They install ransomware and lock up your files. The false flag part? They make it look like another group did it, so you're chasing the wrong lead while they slip away. - The initial contact comes through Microsoft Teams chat - Attackers pose as trusted colleagues or IT support - They send a link to a fake login page - Credentials are stolen and used to deploy ransomware - Evidence is planted to blame another group  ### Why You Should Care About This This isn't just some random attack. MuddyWater has been around for years, and they're known for targeting government agencies, telecom companies, and critical infrastructure. In the United States, that could mean hospitals, power grids, or even local government offices. If you work in IT or manage security for any organization, this is something you need to take seriously. What makes this attack so dangerous is how easy it is to fall for. We all use Microsoft Teams every day. We trust messages from people inside our own company. The hackers are exploiting that trust in a way that feels natural. You don't expect a coworker to try and steal your password.  ### What You Can Do to Protect Yourself First, don't click links in Teams messages unless you're absolutely sure they're real. If the message feels off, even a little bit, verify it through another channel. Call the person or send them an email. It takes an extra minute, but it could save your whole network. Second, enable multi-factor authentication everywhere you can. Even if someone steals your password, MFA can stop them from getting in. It's not perfect, but it's a huge help. Third, train your team. Run drills where you send fake Teams messages to see who clicks. Make it a game, not a punishment. The more people practice spotting these attacks, the less likely they are to fall for the real thing. ### The Bigger Picture This attack shows how cyber threats are evolving. Hackers aren't just breaking in through technical vulnerabilities anymore. They're breaking into your brain. They're using the tools you trust and the routines you follow to get what they want. That's why staying safe means staying skeptical, even when everything looks normal. MuddyWater's use of Microsoft Teams is a wake-up call. If you haven't already, now is the time to review your security policies. Look at how your team handles internal communications. Make sure everyone knows that a friendly message from a colleague could be a trap. Because in the world of cybersecurity, trust is the one thing you can't afford to give away for free.