Name: CVE-2021-42785: Buffer Copy without Checking Size of Input
Creator: Rapid7
Published: 2021-11-23T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2021-42785, CWE-120, CVSS 9.8, EPSS 0.02342

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.

CVSS Details

CVSS 3.1 Base Score: 9.8
CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Ubuntu	—	No solution exists	Jun 26, 2025	Nov 23, 2021

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CVSS Details

Covered by Rapid7

Prioritise with Active Threat Intelligence