CVE-2021-42785

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

Severity Score

9.8

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

*SSVC

Descriptions

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.

Una vulnerabilidad de desbordamiento del búfer en el archivo tvnviewer.exe de TightVNC Viewer permite a un atacante remoto ejecutar instrucciones arbitrarias por medio de un paquete FramebufferUpdate diseñado desde un servidor VNC

*Credits: Eugene Lim from Government Technology Agency of Singapore

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Attack Vector

Network

Attack Complexity

Low

Authentication

None

Confidentiality

Partial

Integrity

Partial

Availability

Partial

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2021-10-21 CVE Reserved
2021-11-23 CVE Published
2024-08-04 CVE Updated
2024-08-08 EPSS Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

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

CAPEC

References (1)

URL	Tag	Source

URL	Date	SRC

URL	Date	SRC

URL	Date	SRC
https://www.tightvnc.com/whatsnew.php	2021-11-29

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Tightvnc Search vendor "Tightvnc"		Tightvnc Search vendor "Tightvnc" for product "Tightvnc"				<= 2.8.59 Search vendor "Tightvnc" for product "Tightvnc" and version " <= 2.8.59"		-		Affected