CVE-2026-111585: Integer Overflow in TeamViewer Viewer

CVE-2026-111585 describes an integer overflow in the remote-control screen processing component of TeamViewer clients (Full Client, Portable, and Remote Control App) prior to version 15.83. A compromised or attacker-controlled host can send malformed data during a remote-control session, exploiting the flaw to cause denial of service or, depending on the platform, execute arbitrary code with the privileges of the viewer process. The impact is critical for organizations using TeamViewer for technical support or remote administration.

The CVSS score is 8.8 (high), assigned by TeamViewer. The vulnerability was published on NVD on October 27, 2026; it is not reported as being actively exploited. However, signals from social media show 5 posts in the last 24 hours and 56 total interactions: the technical community is actively discussing its scope. The flaw is serious because it requires no special privileges from the attacker (AV:N, AC:L, PR:N) and only requires the user to establish a session to a compromised host—a common scenario in technical support.

Immediate action is to update TeamViewer to version 15.83 or later on all systems in use. Until updates are complete, it is advisable to restrict remote-control connections to known hosts whose integrity has been verified. Review connection logs and identify remote sessions to external hosts that were not expected. For organizations where users rely on TeamViewer as a daily work tool, prioritize rolling out the update as soon as possible.