CVE-2019-5636: Beckhoff TwinCAT Discovery Service Denial of Service

Published Nov 21, 2019
·
Updated

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).

Affected Software

2 affected components
Beckhoff Twincat=2.0-build2304
Beckhoff Twincat=3.1-build4024.0

Event History

Nov 21, 2019
CVE Published
via MITRE·07:16 PM
Data Sourced
via MITRE·07:16 PM
DescriptionSeverityWeakness

Frequently Asked Questions

1

What is the severity of CVE-2019-5636?

CVE-2019-5636 has a medium severity level associated with it, indicating it poses a risk of denial of service.

2

How do I fix CVE-2019-5636?

To fix CVE-2019-5636, you should update to TwinCAT 2 version 2304 or TwinCAT 3.1 version 4204.1 or later.

3

What impact does CVE-2019-5636 have on affected systems?

CVE-2019-5636 causes the ADS Discovery Service to shut down when a malformed UDP packet is received, but other TwinCAT functions continue to operate normally.

4

Which versions of TwinCAT are affected by CVE-2019-5636?

CVE-2019-5636 affects TwinCAT 2 version 2304 and all prior versions, as well as TwinCAT 3.1 version 4204.0 and all prior versions.

5

Is a workaround available for CVE-2019-5636?

There is no specific workaround for CVE-2019-5636, but updating to the patched versions is recommended to mitigate the vulnerability.

Contact

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