CVE-2019-5636

Beckhoff TwinCAT Discovery Service Denial of Service

Severity Score

7.5

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

*SSVC

Descriptions

When a Beckhoff TwinCAT Runtime receives a malformed UDP packet, the ADS Discovery Service shuts down. Note that the TwinCAT devices are still performing as normal. This issue affects TwinCAT 2 version 2304 (and prior) and TwinCAT 3.1 version 4204.0 (and prior).

Cuando un Beckhoff TwinCAT Runtime recibe un paquete UDP con formato incorrecto, el servicio de descubrimiento de ADS se cierra. Tenga en cuenta que los dispositivos TwinCAT siguen funcionando normalmente. Este problema afecta a TwinCAT 2 versión 2304 (y anterior) y TwinCAT 3.1 versión 4204.0 (y anterior).

*Credits: This issue was discovered, and reported to Rapid7, by Andreas Galauner at Rapid7. It is being disclosed in accordance with Rapid7's vulnerability disclosure policy (https://www.rapid7.com/disclosure/).

CVSS Scores

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

Low

Attack Vector

Network

Attack Complexity

Low

Authentication

None

Confidentiality

None

Integrity

None

Availability

Partial

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2019-01-07 CVE Reserved
2019-11-21 CVE Published
2023-03-07 EPSS Updated
2024-09-17 CVE Updated
2024-09-17 First Exploit
---------- Exploited in Wild
---------- KEV Due Date

CWE

CWE-404: Improper Resource Shutdown or Release

CAPEC

References (2)

URL	Tag	Source

URL	Date	SRC
https://blog.rapid7.com/2019/10/08/r7-2019-32-denial-of-service-vulnerabilities-in-beckhoff-twincat-plc-environment-fixed	2024-09-17

URL	Date	SRC

URL	Date	SRC
https://download.beckhoff.com/download/Document/product-security/Advisories/advisory-2019-004.pdf	2020-02-04

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Beckhoff Search vendor "Beckhoff"		Twincat Search vendor "Beckhoff" for product "Twincat"				2.0 Search vendor "Beckhoff" for product "Twincat" and version "2.0"		build2304		Affected
Beckhoff Search vendor "Beckhoff"		Twincat Search vendor "Beckhoff" for product "Twincat"				3.1 Search vendor "Beckhoff" for product "Twincat" and version "3.1"		build4024.0		Affected