CVE-2021-34858: TeamViewer

High severity, CVSS 7.8. EPSS: 3.8% chance of exploitation in the next 30 days.

This vulnerability allows remote attackers to execute arbitrary code on affected installations of TeamViewer. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file. The specific flaw exists within the parsing of TVS files. The issue results from the lack of proper validation of user-supplied data, which can result in a read past the end of an allocated structure. An attacker can leverage this vulnerability to execute code in the context of the current process. Was ZDI-CAN-13606.

Affected products

• TeamViewer TeamViewer: before 15.21.2 (fixed in 15.21.2)

Published 2022-01-13. Last modified 2026-06-17.