cvedb.io
CVE-2021-41380
MEDIUM · CVSS 6.5
EPSS exploitation probability: 0%
Published 2021-09-17T20:15:07.827 · Last modified 2026-06-17T04:08:26.977

Summary

RealVNC Viewer 6.21.406 allows remote VNC servers to cause a denial of service (application crash) via crafted RFB protocol data. NOTE: It is asserted that this issue requires social engineering a user into connecting to a fake VNC Server. The VNC Viewer application they are using will then hang, until terminated, but no memory leak occurs - the resources are freed once the hung process is terminated and the resource usage is constant during the hang. Only the process that is connected to the fake Server is affected. This is an application bug, not a security issue

Affected products

realvnc — vnc_viewer

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.