A severe vulnerability in TeamViewer, a widely-used remote-access application, poses a potential threat to IT support systems, cybersecurity experts at Remedio have revealed. This flaw, identified as CVE-2026-111585 with a CVSS score of 8.8, affects various operating systems, including Windows, macOS, Linux, and Android.
Vulnerability Details and Exploitation
The flaw arises from an integer overflow in the remote-control screen processing component of TeamViewer clients. If exploited, attackers could potentially crash the application or run unauthorized code on the viewer’s system. Such exploitation requires a remote session to a host under the attacker’s control, as highlighted in TeamViewer’s advisory.
The root of the issue lies in the way screen dimensions are communicated and processed. A host can declare screen dimensions that overflow the memory allocation for the viewer, leading to potential crashes and unauthorized code execution.
Potential Impacts and Security Risks
According to Remedio, the absence of upper bounds on screen dimensions transmitted over the network enables attackers to take advantage of this flaw. By declaring a screen size beyond standard limits, attackers can cause the viewer application to crash repeatedly. This method leverages standard protocol messages to trigger the vulnerability within an ongoing session.
Beyond causing denial-of-service conditions, the flaw allows for arbitrary code execution on the victim’s system. The vulnerability is exploited by redirecting calls made by the viewer’s application, bypassing existing security measures.
Security Patches and Future Outlook
TeamViewer has addressed this vulnerability in version 15.83, covering various client versions and releasing updates for older software iterations. The updates also fix other critical vulnerabilities, such as CVE-2026-92372 and CVE-2026-92374, which include out-of-bounds write and race condition issues.
While TeamViewer has stated that no known exploits of these vulnerabilities have occurred in the wild, users are urged to update their applications promptly to mitigate potential risks. The company has also patched additional high-severity vulnerabilities related to local privilege escalation in the Remote Management add-ons.
This incident underscores the importance of maintaining up-to-date security practices and regularly applying software updates to protect against emerging threats.
