Ransomware gang abuses Microsoft Teams relays to hide malicious traffic

BleepingComputer
Actively Exploited

Overview

The DragonForce ransomware group has been found using a custom malware called 'Backdoor.Turn' to conceal their command-and-control traffic within Microsoft Teams relays. This tactic allows them to mask their activities, making it harder for security measures to detect their malicious actions. By leveraging the infrastructure of a widely-used collaboration tool, they are able to blend in with legitimate traffic, posing a significant challenge for cybersecurity professionals. This development raises concerns for organizations that utilize Microsoft Teams, as it highlights the potential for trusted platforms to be exploited for harmful purposes. Companies should remain vigilant and enhance their monitoring efforts to detect any unusual activities that could indicate an attack.

Key Takeaways

  • Active Exploitation: This vulnerability is being actively exploited by attackers. Immediate action is recommended.
  • Affected Systems: Microsoft Teams, DragonForce ransomware, Backdoor.Turn malware
  • Action Required: Organizations should implement advanced threat detection systems, regularly monitor network traffic for anomalies, and educate employees about potential phishing attempts that could lead to ransomware infections.
  • Timeline: Newly disclosed

Original Article Summary

DragonForce ransomware used a custom malware named 'Backdoor.Turn' to hide command-and-control traffic inside Microsoft Teams relay infrastructure. [...]

Impact

Microsoft Teams, DragonForce ransomware, Backdoor.Turn malware

Exploitation Status

This vulnerability is confirmed to be actively exploited by attackers in real-world attacks. Organizations should prioritize patching or implementing workarounds immediately.

Timeline

Newly disclosed

Remediation

Organizations should implement advanced threat detection systems, regularly monitor network traffic for anomalies, and educate employees about potential phishing attempts that could lead to ransomware infections.

Additional Information

This threat intelligence is aggregated from trusted cybersecurity sources. For the most up-to-date information, technical details, and official vendor guidance, please refer to the original article linked below.

Related Topics: This incident relates to Ransomware, Microsoft, Malware.

Related Coverage

ShadowPad Malware Actively Exploits WSUS Vulnerability for Full System Access

The Hacker News

The ShadowPad malware is exploiting a recently patched vulnerability in Microsoft Windows Server Update Services (WSUS), identified as CVE-2025-59287, allowing attackers to gain full system access. This exploitation highlights the critical need for organizations to promptly apply security updates to vulnerable systems to prevent unauthorized access.

Nov 24, 2025

⚡ Weekly Recap: Fortinet Exploit, Chrome 0-Day, BadIIS Malware, Record DDoS, SaaS Breach & More

The Hacker News

This week, significant cybersecurity threats emerged as hackers exploited new 0-day vulnerabilities in Fortinet and Chrome, infiltrating supply chains and SaaS tools. The rapid response from major companies like Microsoft, Salesforce, and Google highlights the severity of these attacks and the ongoing challenges in securing trusted applications and software updates.

Nov 24, 2025

Microsoft Highlights Security Risks Introduced by New Agentic AI Feature

SecurityWeek

Microsoft has raised concerns about the security risks associated with its new Agentic AI feature, highlighting the potential for AI agents to engage in malicious activities like data exfiltration and malware installation if not properly secured. This underscores the critical need for robust security controls to mitigate these risks.

Nov 24, 2025

ToddyCat’s New Hacking Tools Steal Outlook Emails and Microsoft 365 Access Tokens

The Hacker News

ToddyCat, a threat actor, has developed a new tool called TCSectorCopy to steal Outlook emails and Microsoft 365 access tokens by exploiting the OAuth 2.0 authorization protocol through users' browsers. This poses a significant threat to corporate email security, as it allows unauthorized access to sensitive information outside the compromised infrastructure.

Nov 25, 2025

Microsoft: Security keys may prompt for PIN after recent updates

BleepingComputer

Microsoft has alerted users that FIDO2 security keys may require a PIN for sign-in following recent Windows updates since September 2025. This change could affect user experience and security practices, particularly for those relying on these security keys for authentication.

Nov 26, 2025

Microsoft to secure Entra ID sign-ins from script injection attacks

BleepingComputer

Microsoft is set to enhance the security of its Entra ID authentication system to protect against external script injection attacks starting in mid-to-late October 2026. This improvement aims to mitigate potential vulnerabilities that could be exploited by attackers to compromise user sign-ins.

Nov 26, 2025