Vulnerability Report

CVE-2021-41380

Title: RealVNC Viewer 6.21.406 allows remote VNC servers to cause a denial of service (application crash) via crafted RFB protocol data.

Denial of Service

Proof Of Concept

No public PoC currently indexed for CVE-2021-41380.

CWE Category CWE-20
Published Date Sep 17, 2021
Modified Date Nov 21, 2024
Exploit Status Not Found
Score 6.5 CVSS v3.1
Exploit Probability (EPSS)
0.96%

Vulnerability Summary

CVE-2021-41380: RealVNC Viewer 6.21.406 allows remote VNC servers to cause a denial of service (application crash) via crafted RFB protocol data. NOTE: It is asserted that this issue requires social engineering a user into connecting to a fake VNC Server. The VNC Viewer application they are using will then hang, until terminated, but no memory leak occurs - the resources are freed once the hung process is terminated and the resource usage is constant during the hang. Only the process that is connected to the fake Server is affected. This is an application bug, not a security issue

Impacted Vendors

U
ultravnc 1
R
realvnc 1

Reference Links

https://gist.github.com/totaam/a90f2bb40f5b693ccec0ae903d021b03 https://gist.github.com/totaam/a90f2bb40f5b693ccec0ae903d021b03
CVSS v3.1
Source Entity [email protected]
Severity MEDIUM
6.5
Attack Vector
NETWORK
Complexity
LOW
Privileges
N/A
Interaction
REQUIRED
Confidentiality
N/A
Integrity
N/A
Availability
N/A
Scope
UNCHANGED
RAW VECTOR CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
CVSS v2.0
Source Entity [email protected]
Severity MEDIUM
4.3
Access Vector
N/A
Authentication
N/A
RAW VECTOR AV:N/AC:M/Au:N/C:N/I:N/A:P

Associated Attack Patterns (CAPEC)

Total: Patterns

CVE-2021-41380 Exploits & PoCs (Proof Of Concept)

No public PoCs found in our database for this CVE.

MODIFIED

Vulnerability data or affected products updated.

PUBLISHED

Vulnerability first announced in NVD.

Attack Vector Matrix

Access Vector NETWORK
Complexity LOW
Privileges N/A
Interaction REQUIRED
CVSS Vector String CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

Affected Stack

No specific products linked.