The Swabian software company Teamviewer claims to have been the victim of a hacker attack.

On Wednesday, the company's IT was attacked using an employee's login data, the company announced on Friday. "Based on continuous security monitoring, our teams detected suspicious behavior of the account and immediately took countermeasures," it said in the message to customers, which Teamviewer published on its homepage. According to current findings, the Russian hacker group APT29, which also operates as "Midnight Blizzard" and allegedly acts on behalf of the Russian government, is behind the attack.

The news weighed on the shares of the manufacturer of remote control and remote maintenance software. It slumped by more than nine percent on Friday to an annual low of 10.11 euros.

TeamViewer had initially only reported "an anomaly in our internal IT environment". According to the information available so far, the cyberattack was limited to Teamviewer's internal IT, the updated statement said. "There are no indications that the attackers have gained access to our product environment or customer data." The servers, networks and accounts were always kept strictly separate.

(Report by Alexander Hübner, edited by Myria Mildenberger. If you have any questions, please contact our editorial team at berlin.newsroom@thomsonreuters.com (for politics and the economy) or frankfurt.newsroom@thomsonreuters.com (for companies and markets).