CVE-2020-12494: beckhoff twincat Incomplete Cleanup

Vulnerability summary

CVE-2020-12494 is a medium (CVSS 5.3) Incomplete Cleanup vulnerability in beckhoff twincat. EPSS estimates a 1.01% chance of exploitation in the next 30 days, higher than 62.8% of scored vulnerabilities.

Timeline

1. 16-06-2020
   PublishedVulnerability first disclosed.
2. 04-08-2024
   Last modifiedVulnerability information updated.

Description

Beckhoff's TwinCAT RT network driver for Intel 8254x and 8255x is providing EtherCAT functionality. The driver implements real-time features. Except for Ethernet frames sent from real-time functionality, all other Ethernet frames sent through the driver are not padded if their payload is less than the minimum Ethernet frame size. Instead, arbitrary memory content is transmitted within in the padding bytes of the frame. Most likely this memory contains slices from previously transmitted or received frames. By this method, memory content is disclosed, however, an attacker can hardly control which memory content is affected. For example, the disclosure can be provoked with small sized ICMP echo requests sent to the device.

• CWE-459Incomplete CleanupThe product does not properly "clean up" and remove temporary or supporting resources after they have been used.