OTPulse

Advant Master Online Builder DLL vulnerability

MonitorCVSS 4.47paa020047Jun 23, 2026
ABB
Attack path
Attack VectorLocal
Auth RequiredLow
ComplexityHigh
User InteractionRequired
Summary

ABB identified a DLL vulnerability in the Online Builder component shipped with multiple versions of Control Builder A and 800xA for Advant Master. An incorrect version of Online Builder was included in the release media, allowing potential code execution when the application loads a malicious DLL file. The vulnerability requires local system access and user action to exploit. ABB has released patched versions that include the correct Online Builder component.

What this means
What could happen
An attacker with local access to a system could exploit a malicious DLL file to perform unauthorized actions on the affected ABB control systems, potentially altering configurations or disrupting operations.
Who's at risk
ABB Advant Master operators and Control Builder users managing process automation and control systems. This affects facilities using 800xA engineering and control platforms for process monitoring and command execution.
How it could be exploited
An attacker with local system access could place a malicious DLL file that gets loaded by the Online Builder component during system initialization or application startup. When a user runs the affected application, the malicious DLL executes with the user's privileges, allowing code execution on the control system.
Prerequisites
  • Local access to the affected system
  • User with privileges to log on to the system must run the application
  • Ability to place files in a location where the Online Builder searches for DLLs
Local access requiredLow complexityUser interaction requiredAffects process control integrity
Exploitability
Unlikely to be exploited — EPSS score 0.1%
Affected products (5)
5 with fix
ProductAffected VersionsFix Status
Control Builder A <=1.4/4≤ 1.4/41.4/5
800xA for Advant Master <=6.0.3-1≤ 6.0.3-1Fix available
800xA for Advant Master <=6.1.1-1≤ 6.1.1-1Fix available
800xA for Advant Master 6.1.1-36.1.1-3Fix available
800xA for Advant Master 6.2.0-16.2.0-1Fix available
Remediation & Mitigation
0/6
Do now
0/3
HARDENINGRestrict system access to only authorized users with strong passwords that are changed regularly
HARDENINGDisable or manage USB ports and removable media devices to prevent unauthorized DLL file insertion
HARDENINGRestrict temporary connections of portable computers and external devices to the control system
Schedule — requires maintenance window
0/3

Patching may require device reboot — plan for process interruption

HOTFIXUpdate Control Builder A to version 1.4/5 or later
HOTFIXUpdate 800xA for Advant Master versions 6.0.3-1, 6.1.1-1, 6.1.1-2, 6.1.1-3, or 6.1.1-4 to version 6.1.1-5 or later
HOTFIXUpdate 800xA for Advant Master versions 6.2.0-1 or 6.2.0-2 to version 6.2.0-3 or later
View full ABB PSIRT advisory
API: /api/v1/advisories/feb4f902-105f-4f28-bd22-f457eedf4dab

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