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Mitsubishi Electric GOT and Tension Controller (Update A)

MonitorCVSS 5.9ICS-CERT ICSA-21-131-02May 11, 2021
Mitsubishi ElectricEnergy
Attack path
Attack VectorNetwork
Auth RequiredNone
ComplexityHigh
User InteractionNone needed
Summary

A buffer overflow vulnerability in Mitsubishi Electric GOT operator interface panels and LE7-40GU-L Tension Controllers allows a remote attacker on the network to send a specially crafted packet that disrupts the device's communication function. The affected device will stop communicating with controllers and systems and will require a manual reset to restore functionality. The vulnerability requires high attack complexity and no authentication, but affects multiple models of operator interface devices commonly used for production monitoring and control in industrial environments.

What this means
What could happen
An attacker could disrupt communication on Mitsubishi Electric operator interface panels (GOT series) and tension controllers, forcing a manual reset to restore operations. This could halt production monitoring and process control until the device is rebooted.
Who's at risk
Energy sector operators running Mitsubishi Electric GOT operator interface panels (GT23, GT21, GT25, GT27 models, GS21, SoftGOT2000) and LE7-40GU-L Tension Controllers with MODBUS/TCP connectivity should assess exposure. These devices are typically used for real-time process monitoring and control on production equipment and critical infrastructure.
How it could be exploited
An attacker on the network sends a specially crafted packet or sequence of requests to a GOT device running a vulnerable firmware version. The malformed input causes the communication function to fail, stopping the device from communicating with connected controllers and systems until manually reset.
Prerequisites
  • Network access to the GOT device or Tension Controller
  • Device running vulnerable firmware version (see affected products)
  • High attack complexity; attacker must craft specific malformed input
remotely exploitableno authentication requiredaffects production monitoring and control systemsrequires reset to restore operations
Exploitability
Unlikely to be exploited — EPSS score 0.3%
Affected products (7)
7 with fix
ProductAffected VersionsFix Status
GT23 model:≥ 01.19.000 | ≤ 01.38.00001.40.000
LE7-40GU-L Screen package data for MODBUS/TCP: v1.00101.40.000
GS21 model:≥ 01.21.000 | ≤ 01.39.00001.40.000
GT27 model:≥ 01.19.000 | ≤ 01.38.00001.40.000
GT25 model:≥ 01.19.000 | ≤ 01.38.00001.40.000
GT SoftGOT2000:≥ 1.170C | ≤ 1.250L01.40.000
GT21 model:≥ 01.21.000 | ≤ 01.39.00001.40.000
Remediation & Mitigation
0/7
Do now
0/1
WORKAROUNDRestrict network access to GOT devices using firewall rules; block inbound traffic from untrusted networks on the ports used by these devices
Schedule — requires maintenance window
0/5

Patching may require device reboot — plan for process interruption

HOTFIXUpdate GOT2000 GT27, GT25, and GT23 models to firmware version 01.39.000 or later
HOTFIXUpdate GOT2000 GT21 model to firmware version 01.40.000 or later
HOTFIXUpdate GOT SIMPLE GS21 model to firmware version 01.40.000 or later
HOTFIXUpdate GT SoftGOT2000 to version 1.255R or later
HOTFIXUpdate LE7-40GU-L Screen package data for MODBUS/TCP to v1.01 or later
Long-term hardening
0/1
HARDENINGIsolate GOT devices to the local plant network (LAN); do not expose to the Internet or untrusted network segments
View full CISA ICS-CERT advisory
API: /api/v1/advisories/5c1e456a-1828-4973-824c-1e46ef621476

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Mitsubishi Electric GOT and Tension Controller (Update A) | CVSS 5.9 - OTPulse