Beckhoff Twincat Improper Resource Shutdown or Release

high Tenable.ot Plugin ID 500343
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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).


Refer to vendor advisory for Security Updates

See Also

Plugin Details

Severity: High

ID: 500343

Version: 1.0

Type: local

Family: SCADA

Published: 5/27/2020

Updated: 5/27/2020

Risk Information

CVSS Score Source: CVE-2019-5636


Risk Factor: Medium

Base Score: 5

Vector: AV:N/AC:L/Au:N/C:N/I:N/A:P


Risk Factor: High

Base Score: 7.5

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Vulnerability Information

CPE: cpe:2.3:a:beckhoff:twincat:2.0:build2304:*:*:*:*:*:*, cpe:2.3:a:beckhoff:twincat:3.1:build4024.0:*:*:*:*:*:*

Patch Publication Date: 11/21/2019

Vulnerability Publication Date: 11/21/2019

Reference Information

CVE: CVE-2019-5636