CVE-2019-5636

Public Exploit
Beckhoff TwinCAT Discovery Service Denial of Service

Description

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).

Category

5.3
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.54%
Vendor Advisory beckhoff.com
Affected: Beckhoff TwinCAT 2
Affected: Beckhoff TwinCAT 3.1
Published at:
Updated at:

References

Link Tags
https://download.beckhoff.com/download/Document/product-security/Advisories/advisory-2019-004.pdf vendor advisory
https://blog.rapid7.com/2019/10/08/r7-2019-32-denial-of-service-vulnerabilities-in-beckhoff-twincat-plc-environment-fixed/ third party advisory exploit

Frequently Asked Questions

What is the severity of CVE-2019-5636?
CVE-2019-5636 has been scored as a medium severity vulnerability.
How to fix CVE-2019-5636?
To fix CVE-2019-5636, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2019-5636 being actively exploited in the wild?
It is possible that CVE-2019-5636 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2019-5636?
CVE-2019-5636 affects Beckhoff TwinCAT 2, Beckhoff TwinCAT 3.1.
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