CVE-2020-12011

Vulnerability

An out-of-bounds write vulnerability (CWE-787) exists in the GenBroker64 and GenBroker32 components of Mitsubishi Electric MC Works64 version 4.02C (10.95.208.31) and earlier, MC Works32 version 3.00A (9.50.255.02), and ICONICS GENESIS64 (GenBroker64, Platform Services, Workbench, FrameWorX Server) version 10.96 and prior, as well as GENESIS32 (GenBroker32) version 9.5 and prior [1][2]. A specially crafted communication packet sent to the affected Broker services triggers the out-of-bounds write.

Exploitation

An unauthenticated attacker can exploit this vulnerability remotely over the network without user interaction. The attack complexity is high (CVSSv3 AC:H), meaning the attacker must craft a precise malicious packet to trigger the write. The packet is sent to the listening Broker64 or Broker32 service on the affected system [1][2].

Impact

Successful exploitation can lead to a denial-of-service condition or remote code execution. The CVSSv3 base score is 8.1 with vector (AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H), indicating high impact on confidentiality, integrity, and availability [1][2].

Mitigation

Mitsubishi Electric recommends updating MC Works64 and MC Works32 to the latest versions [1]. ICONICS recommends updating GENESIS64 and GENESIS32 to the latest versions [2]. Users should also apply network segmentation and restrict access to affected services as a defense-in-depth measure. No workaround is provided other than updating.