SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2021-41380

RealVNC Viewer 6.21.406 allows remote VNC servers to cause a denial of service (application crash) via crafted RFB protocol data.

MEDIUM 6.5EPSS 0.96%

Does this matter?

Lower severity and a low EPSS score (0.96%). Track it; it rarely justifies an emergency change on its own.

Description

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

CVSS 3.1
6.5 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
EPSS
0.96% probability · 59th percentile
CISA KEV
Not listed
Weakness
CWE-20
Affected
realvnc/vnc viewer
Source
cve@mitre.org

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.