CVE-2021-41380

Public Exploit

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

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.29%
Third-Party Advisory github.com
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://gist.github.com/totaam/a90f2bb40f5b693ccec0ae903d021b03 third party advisory exploit

Frequently Asked Questions

What is the severity of CVE-2021-41380?
CVE-2021-41380 has been scored as a medium severity vulnerability.
How to fix CVE-2021-41380?
To fix CVE-2021-41380, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-41380 being actively exploited in the wild?
It is possible that CVE-2021-41380 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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