Breach of TeamViewer

The remote access software company TeamViewer has confirmed a cyberattack on its corporate environment, allegedly carried out by an Advanced Persistent Threat (APT) hacking group. This incident has raised significant concerns given TeamViewer's extensive use in both consumer and corporate settings.

Detection and Response

On June 26, 2024, TeamViewer's security team detected an irregularity in their internal corporate IT environment. In a statement posted on their Trust Center, the company detailed their immediate response:

"We immediately activated our response team and procedures, started investigations together with a team of globally renowned cybersecurity experts, and implemented necessary remediation measures."

TeamViewer emphasized that their internal corporate IT environment operates independently from their product environment, asserting that there is no evidence to suggest the product environment or customer data has been affected. However, the investigation is ongoing, and their primary focus remains on ensuring system integrity.

Transparency and Challenges

TeamViewer has pledged to maintain transparency about the breach and to continuously update the status of their investigation. However, a notable detail is that their "TeamViewer IT security update" page includes a <meta name="robots" content="noindex"> HTML tag, which prevents the document from being indexed by search engines, making it difficult for users to find the updates.

The Scope of TeamViewer’s Usage

TeamViewer is widely used for remote access, allowing users to control a computer as if they were physically present. With over 640,000 customers worldwide and installations on more than 2.5 billion devices, any breach poses a substantial risk as it could potentially provide full access to internal networks.

Alleged APT Group Involvement

The breach was initially reported on Mastodon by IT security professional Jeffrey, who shared alerts from the Dutch Digital Trust Center. According to an alert from the IT security firm NCC Group:

"The NCC Group Global Threat Intelligence team has been made aware of significant compromise of the TeamViewer remote access and support platform by an APT group."

An alert from Health-ISAC also warned that TeamViewer services are allegedly being actively targeted by the Russian hacking group APT29, also known as Cozy Bear, NOBELIUM, and Midnight Blizzard. The Health-ISAC alert recommended reviewing logs for unusual remote desktop traffic, noting:

"APT29 is actively exploiting Teamviewer."

APT29, linked to Russia's Foreign Intelligence Service (SVR), is notorious for its cyberespionage activities, including attacks on Western diplomats and a recent breach of Microsoft's corporate email environment.


While TeamViewer assures users that there is no evidence of customer data being compromised, the breach highlights the risks associated with widely used remote access tools. Continuous updates from TeamViewer and vigilant monitoring of remote desktop traffic are essential as the situation evolves.

For more details and updates, visit the official statements from TeamViewer and trusted cybersecurity sources.

Credit: Information provided by BleepingComputer