OTPulse

Helmholz: Multiple vulnerabilities in REX 100

MonitorCVSS 7.2VDE-2025-059Jul 21, 2025
Helmholz
Attack path
Attack VectorNetwork
Auth RequiredHigh
ComplexityLow
User InteractionNone needed
Summary

Multiple vulnerabilities exist in Helmholz REX 100 devices with firmware versions 2.3.2 and earlier, including command injection (CWE-78), SQL injection (CWE-89), buffer overflow (CWE-787), cross-site scripting (CWE-79), and resource exhaustion (CWE-400). These vulnerabilities allow an authenticated attacker to gain full control over the device. Firmware version 2.3.3 or later contains fixes for these issues.

What this means
What could happen
An attacker with valid credentials to a REX 100 device can execute arbitrary commands or alter device configuration, potentially disrupting process automation or data logging in the plant.
Who's at risk
Operations managers and automation technicians responsible for Helmholz REX 100 controllers used in manufacturing, process automation, or facility management systems should assess whether they are running vulnerable firmware versions and take steps to restrict access and apply updates.
How it could be exploited
An attacker must first obtain valid login credentials for the REX 100 device, then can exploit the vulnerabilities (command injection, SQL injection, buffer overflow, or XSS) to gain full control of the device and execute arbitrary commands on the system.
Prerequisites
  • Valid login credentials for the REX 100 device (username and password)
  • Network access to the REX 100 device management interface
  • Device firmware version 2.3.2 or earlier
remotely exploitablerequires valid credentialsaffects multiple attack vectors (CWE-78 command injection, CWE-89 SQL injection, CWE-787 buffer overflow)vendor fix available
Exploitability
Unlikely to be exploited — EPSS score 0.2%
Affected products (1)
ProductAffected VersionsFix Status
Firmware <2.3.3All versionsFix available
Remediation & Mitigation
0/3
Do now
0/2
HARDENINGVerify that 'Lock network configuration (Conftool)' is enabled in device configuration
HARDENINGRestrict network access to REX 100 device management interface to authorized personnel only; use firewall rules to limit access to trusted engineering workstations
Schedule — requires maintenance window
0/1

Patching may require device reboot — plan for process interruption

HOTFIXUpdate REX 100 firmware to version 2.3.3 or later
View full CERT@VDE advisory
API: /api/v1/advisories/948b7410-6bbb-472c-bf2d-1d7dc832e979

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Helmholz: Multiple vulnerabilities in REX 100 | CVSS 7.2 - OTPulse