CVE-2020-12494

Summary

CVECVE-2020-12494
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2020-06-16 14:15:00 UTC
Updated2021-12-02 19:31:00 UTC
DescriptionBeckhoff'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.

Risk And Classification

Problem Types: CWE-459

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Application Beckhoff Twincat 2.11 build_2350 All All
Application Beckhoff Twincat 3.1 build_402 All All
Application Beckhoff Twincat 3.1 build_4022 All All
Application Beckhoff Twincat 3.1 build_4024 All All
Application Beckhoff Twincat 2.11 build_2350 All All
Application Beckhoff Twincat 3.1 build_402 All All
Application Beckhoff Twincat 3.1 build_4022 All All
Application Beckhoff Twincat 3.1 build_4024 All All
Application Beckhoff Twincat All All All All
Application Beckhoff Twincat All All All All
Application Beckhoff Twincat All All All All
Application Beckhoff Twincat All All All All
Application Beckhoff Twincat All All All All
Application Beckhoff Twincat Driver All All All All
Hardware Intel 82540em - All All All
Hardware Intel 82540em - All All All
Hardware Intel 82540ep - All All All
Hardware Intel 82540ep - All All All
Hardware Intel 82541ei - All All All
Hardware Intel 82541ei - All All All
Hardware Intel 82541er - All All All
Hardware Intel 82541er - All All All
Hardware Intel 82541gi - All All All
Hardware Intel 82541gi - All All All
Hardware Intel 82541pi - All All All
Hardware Intel 82541pi - All All All
Hardware Intel 82544ei - All All All
Hardware Intel 82544ei - All All All
Hardware Intel 82544gc - All All All
Hardware Intel 82544gc - All All All
Hardware Intel 82545em - All All All
Hardware Intel 82545em - All All All
Hardware Intel 82545gm - All All All
Hardware Intel 82545gm - All All All
Hardware Intel 82546eb - All All All
Hardware Intel 82546eb - All All All
Hardware Intel 82546gb - All All All
Hardware Intel 82546gb - All All All
Hardware Intel 82547ei - All All All
Hardware Intel 82547ei - All All All
Hardware Intel 82547ei - All All All
Hardware Intel 82547ei - All All All
Hardware Intel 82547gi - All All All
Hardware Intel 82547gi - All All All
Hardware Intel 82557 - All All All
Hardware Intel 82557 - All All All
Hardware Intel 82558 - All All All
Hardware Intel 82558 - All All All
Hardware Intel 82559 - All All All
Hardware Intel 82559 - All All All

References

ReferenceSourceLinkTags
BECKHOFF: EtherLeak in TwinCAT RT network driver — English (USA) CONFIRM cert.vde.com Third Party Advisory
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Vendor Comments And Credit

Discovery Credit

LEGACY: Beckhoff reported this vulnerability to CERT@VDE

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