CVE-2021-42785: Buffer Overflow in tvnviewer.exe via Crafted Packet in TightVNC Viewer 2.8.59

Published Nov 23, 2021
·
Updated

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.

Affected Software

1 affected component
TightVNC TightVnc<=2.8.59

Event History

Nov 23, 2021
CVE Published
via MITRE·09:37 PM
Data Sourced
via MITRE·09:37 PM
DescriptionWeakness
Data Sourced
via NVD·10:15 PM
DescriptionSeverityWeaknessAffected Software
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Frequently Asked Questions

1

What is CVE-2021-42785?

CVE-2021-42785 is a buffer overflow vulnerability in tvnviewer.exe of TightVNC Viewer.

2

How does CVE-2021-42785 affect TightVNC Viewer?

CVE-2021-42785 allows a remote attacker to execute arbitrary instructions via a crafted FramebufferUpdate packet from a VNC server.

3

What is the severity of CVE-2021-42785?

CVE-2021-42785 has a severity rating of 9.8, which is considered critical.

4

Which version of TightVNC Viewer is affected by CVE-2021-42785?

TightVNC Viewer version 2.8.59 is affected by CVE-2021-42785.

5

How can I fix CVE-2021-42785?

To fix CVE-2021-42785, update TightVNC Viewer to a version that is not affected by the vulnerability.

Contact

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