CVE-2021-42785 - Vulnerability Details - OpenCVE

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.

Published: 2021-11-23

Score: 9.8 Critical

EPSS: 2.3% Low

KEV: No

Impact:

Action:

Analysis

Analysis and contextual insights are available on OpenCVE Cloud.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

GlavSoft LLC

TightVNC Viewer

affected

Version	Status	Constraints
`2.8.59`	affected	≤ 2.8.59

Configuration 1 [-]

cpe:2.3:a:tightvnc:tightvnc:*:*:*:*:*:*:*:*

No data.

No data available yet.

Remediation

No vendor fix or workaround currently provided.

Additional remediation guidance may be available on OpenCVE Cloud.

Tracking

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Advisories

Source	ID	Title
EUVD	EUVD-2021-29741	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.

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

Availability Impact High

User Interaction None

No CVSS v3.0

Access Vector Network

Access Complexity Low

Authentication None

Confidentiality Impact Partial

Integrity Impact Partial

Availability Impact Partial

This CVE is not in the KEV list.

The EPSS score is 0.02267.

Key SSVC decision points have not yet been added.

References

Link	Providers
https://www.tightvnc.com/whatsnew.php

History

No history.

Subscriptions

Tightvnc Tightvnc

MITRE

Status: PUBLISHED

Assigner: GovTech CSG

Published: 2021-11-23T21:37:07.000Z

Updated: 2024-08-04T03:38:50.226Z

Reserved: 2021-10-21T00:00:00.000Z

Link: CVE-2021-42785

Vulnrichment

No data.

NVD

Status : Modified

Published: 2021-11-23T22:15:08.133

Modified: 2026-06-17T04:10:08.660

Link: CVE-2021-42785

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-120
Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

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