The Hidden Dangers of Legitimate Tools: Weaponizing TeamViewer


The increasing trend of cybercriminals exploiting legitimate software like TeamViewer for malicious activities, particularly ransomware attacks, poses a significant threat to organizations worldwide. Despite TeamViewer’s widespread legitimate use in the business world, its misuse by attackers reveals the darker side of remote access technologies.

The Exploitation of TeamViewer

TeamViewer, a highly regarded tool for remote access, has unfortunately become a tool for cybercriminals. These attackers use TeamViewer to gain initial access to organization endpoints, attempting to deploy ransomware based on the leaked LockBit ransomware builder. This misuse is not new; a similar situation occurred in 2016 with the Surprise ransomware, indicating a recurring problem.

How the Attacks Occur

The process involves attackers gaining control over TeamViewer instances on victim endpoints. They typically use leaked credentials to access devices, bypassing the need to exploit any security vulnerabilities in TeamViewer itself. This method, known as credential stuffing, leverages the widespread usage of TeamViewer and the tendency of users to reuse passwords.

The Impact and Response

These attacks have led to successful ransomware deployments in some cases, while in others, security measures have thwarted the attempts. The attackers generally try to deploy the ransomware payload using a DOS batch file, which executes a malicious DLL file. Although cybersecurity experts like Huntress have identified these patterns, attributing the attacks to specific ransomware gangs remains challenging.

Securing Against These Threats

To combat this misuse, TeamViewer emphasizes the importance of robust security practices, including using complex passwords, two-factor authentication, allow-lists, and regular software updates. TeamViewer also offers guidelines for secure unattended access, aiming to bolster the security posture of its users against such unauthorized access.


The abuse of TeamViewer for ransomware attacks is a stark reminder of the potential vulnerabilities in using remote access tools. Organizations and individuals using such tools must be vigilant, update their software regularly, and implement strong security measures to protect against these sophisticated cyber threats.


– ‘TeamViewer abused to breach networks in new ransomware attacks’:
– ‘TeamViewer being used to breach networks in Ransomware attacks’: