CVE-2021-42785

Buffer Overflow in tvnviewer.exe via Crafted Packet in TightVNC Viewer 2.8.59

Description

Buffer Overflow vulnerability in tvnviewer.exe of TightVNC Viewer allows a remote attacker to execute arbitrary instructions via a crafted FramebufferUpdate packet from a VNC server.

Category

9.8
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.99% Top 25%
Vendor Advisory tightvnc.com
Affected: GlavSoft LLC TightVNC Viewer
Published at:
Updated at:

References

Link Tags
https://www.tightvnc.com/whatsnew.php release notes vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-42785?
CVE-2021-42785 has been scored as a critical severity vulnerability.
How to fix CVE-2021-42785?
To fix CVE-2021-42785, 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-2021-42785 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-42785 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-42785?
CVE-2021-42785 affects GlavSoft LLC TightVNC Viewer.
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