cve.bz

CVE-2021-41380

6.5 mediumEPSS 1.0%

Medium (6.5) in realvnc vnc viewer. EPSS 1.0% chance of exploitation in the next 30 days.

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

Severity

CVSS 3.1

6.5 medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
EPSS
1.0% chance of exploitation in the next 30 days; higher than 61% of CVEs (scores of 2026-10-31)
CWE
CWE-20
Published
Modified
Record from
the NVD, synced

Affected

References

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