{"document":{"acknowledgments":[{"organization":"CERT@VDE","summary":"coordination"}],"category":"csaf_security_advisory","csaf_version":"2.0","distribution":{"tlp":{"label":"WHITE","url":"https://www.first.org/tlp/"}},"lang":"en-GB","notes":[{"category":"summary","text":"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.","title":"Summary"},{"category":"description","text":"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.","title":"Impact"},{"category":"description","text":"Beckhoff offers software patches for TwinCAT 3.1 and TwinCAT 2.11 on request. These patches will be included in the the next regular releases to the affected software versions.","title":"Remediation"},{"category":"description","text":"If no real-time communication from TwinCAT is required on the Ethernet interface, then users can alternatively re-configure them to use the Intel ® driver, which is shipped with Beckhoff images.\n\nCustomers should configure a perimeter firewall to block traffic from untrusted networks to the device, especially regarding ICMP and other small ethernet frames.","title":"Mitigation"}],"publisher":{"category":"vendor","contact_details":"product-securityincident@beckhoff.com","name":"Beckhoff Automation GmbH & Co. KG","namespace":"https://www.beckhoff.com"},"references":[{"category":"external","summary":"CERT@VDE Security Advisories for Beckhoff Automation GmbH & Co. KG","url":"https://certvde.com/en/advisories/vendor/beckhoff/"},{"category":"self","summary":"VDE-2020-019: Beckhoff: EtherLeak in TwinCAT RT network driver - HTML","url":"https://certvde.com/de/advisories/VDE-2020-019/"},{"category":"self","summary":"VDE-2020-019: Beckhoff: EtherLeak in TwinCAT RT network driver - CSAF","url":"https://beckhoff.csaf-tp.certvde.com/.well-known/csaf/white/2020/vde-2020-019.json"}],"title":"Beckhoff: EtherLeak in TwinCAT RT network driver","tracking":{"aliases":["VDE-2020-019"],"current_release_date":"2025-05-22T13:03:10.000Z","generator":{"date":"2025-04-11T07:22:18.684Z","engine":{"name":"Secvisogram","version":"2.5.23"}},"id":"VDE-2020-019","initial_release_date":"2020-06-16T08:31:00.000Z","revision_history":[{"date":"2020-06-16T08:31:00.000Z","number":"1","summary":"Initial revision."},{"date":"2024-11-06T11:27:01.000Z","number":"2","summary":"Fix: added self-reference"},{"date":"2025-04-11T07:00:00.000Z","number":"3","summary":"Fix: version range"},{"date":"2025-05-22T13:03:10.000Z","number":"4","summary":"Fix: added distribution, quotation mark"}],"status":"final","version":"4"}},"product_tree":{"branches":[{"branches":[{"branches":[{"branches":[{"branches":[{"category":"product_version_range","name":"<=2.11.0.2120","product":{"name":"TwinCAT Driver for Intel 8254x TwinCAT 2.11 2350 <=2.11.0.2120","product_id":"CSAFPID-51001"}}],"category":"product_name","name":"TwinCAT 2.11 2350"},{"branches":[{"category":"product_version_range","name":"<=3.1.0.3512","product":{"name":"TwinCAT Driver for Intel 8254x TwinCAT 3.1 4022 <=3.1.0.3512","product_id":"CSAFPID-51002"}}],"category":"product_name","name":"TwinCAT 3.1 4022"},{"branches":[{"category":"product_version_range","name":"<=3.1.0.3603","product":{"name":"TwinCAT Driver for Intel 8254x TwinCAT 3.1 4024 <=3.1.0.3603","product_id":"CSAFPID-51003"}}],"category":"product_name","name":"TwinCAT 3.1 4024"}],"category":"product_family","name":"TwinCAT Driver for Intel 8254x"},{"branches":[{"branches":[{"category":"product_version_range","name":"<=2.11.0.2117","product":{"name":"TwinCAT Driver for Intel 8255x TwinCAT 2.11 2350 <=2.11.0.2117","product_id":"CSAFPID-51004"}}],"category":"product_name","name":"TwinCAT 2.11 2350"},{"branches":[{"category":"product_version_range","name":"<=3.1.0.3600","product":{"name":"TwinCAT Driver for Intel 8255x TwinCAT 3.1 402 <=3.1.0.3600","product_id":"CSAFPID-51005"}}],"category":"product_name","name":"TwinCAT 3.1 402"},{"branches":[{"category":"product_version_range","name":"<=3.1.0.3500","product":{"name":"TwinCAT Driver for Intel 8255x TwinCAT 3.1 4024 <=3.1.0.3500","product_id":"CSAFPID-51006"}}],"category":"product_name","name":"TwinCAT 3.1 4024"}],"category":"product_name","name":"TwinCAT Driver for Intel 8255x"}],"category":"product_family","name":"Software"}],"category":"vendor","name":"Beckhoff"}]},"vulnerabilities":[{"cve":"CVE-2020-12494","cwe":{"id":"CWE-200","name":"Exposure of Sensitive Information to an Unauthorized Actor"},"notes":[{"category":"description","text":"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.","title":"Vulnerability Description"}],"product_status":{"known_affected":["CSAFPID-51001","CSAFPID-51002","CSAFPID-51003","CSAFPID-51004","CSAFPID-51005","CSAFPID-51006"]},"remediations":[{"category":"vendor_fix","details":"Beckhoff offers software patches for TwinCAT 3.1 and TwinCAT 2.11 on request. These patches will be included in the the next regular releases to the affected software versions. The advisory will be updated upon availability.","product_ids":["CSAFPID-51001","CSAFPID-51002","CSAFPID-51003","CSAFPID-51004","CSAFPID-51005","CSAFPID-51006"]},{"category":"mitigation","details":"If no real-time communication from TwinCAT is required on the Ethernet interface, then users can alternatively re-configure them to use the Intel ® driver, which is shipped with Beckhoff images.\n\nCustomers should configure a perimeter firewall to block traffic from untrusted networks to the device, especially regarding ICMP and other small ethernet frames.","product_ids":["CSAFPID-51001","CSAFPID-51002","CSAFPID-51003","CSAFPID-51004","CSAFPID-51005","CSAFPID-51006"]}],"scores":[{"cvss_v3":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":5.3,"baseSeverity":"MEDIUM","confidentialityImpact":"LOW","environmentalScore":5.3,"environmentalSeverity":"MEDIUM","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","temporalScore":5.3,"temporalSeverity":"MEDIUM","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","version":"3.1"},"products":["CSAFPID-51001","CSAFPID-51002","CSAFPID-51003","CSAFPID-51004","CSAFPID-51005","CSAFPID-51006"]}],"title":"CVE-2020-12494"}]}