CVE-2025-7971 Overview
CVE-2025-7971 affects Rockwell Automation Studio 5000 Logix Designer. The vulnerability stems from unsafe handling of environment variables within the application. When the specified environment variable path lacks a valid file, Logix Designer crashes. Under specific conditions, an attacker can leverage this improper input validation flaw [CWE-20] to execute malicious code without triggering the expected crash.
The issue requires local access and low privileges, but user interaction is also needed. Successful exploitation compromises confidentiality, integrity, and availability of the engineering workstation running Studio 5000.
Critical Impact
Local attackers with limited privileges can achieve arbitrary code execution on engineering workstations used to program Rockwell Automation programmable logic controllers.
Affected Products
- Rockwell Automation Studio 5000 Logix Designer
- Engineering workstations running vulnerable Logix Designer versions
- Industrial control system environments using Studio 5000 for PLC programming
Discovery Timeline
- 2025-08-14 - CVE-2025-7971 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-7971
Vulnerability Analysis
Studio 5000 Logix Designer reads environment variables to resolve file paths during execution. The application does not properly validate or sanitize the values referenced by these environment variables. When Logix Designer encounters a path that does not resolve to a valid file, the process crashes as an unhandled error condition.
The more serious behavior occurs when an attacker crafts the environment variable to reference an attacker-controlled file or resource. In that scenario, the application loads and executes attacker-supplied content without failure, resulting in arbitrary code execution in the context of the Logix Designer process. The root weakness is classified as Improper Input Validation [CWE-20].
Engineering workstations are high-value targets in operational technology (OT) networks. Code execution on these systems can lead to modification of PLC logic, disruption of industrial processes, and lateral movement into control networks.
Root Cause
The root cause is missing validation on environment variable values that influence file loading. Logix Designer trusts the resolved path without verifying file provenance, integrity, or expected location. An attacker who can set or modify environment variables in the user session controls what the application loads.
Attack Vector
The attack requires local access to the workstation and low-privilege user context. The attacker sets a malicious environment variable, then triggers user interaction that causes Logix Designer to consult the variable. When the application resolves the crafted path, it either crashes or executes attacker-controlled code depending on the file placement. See the Rockwell Automation Security Advisory SD1734 for vendor-specific technical details.
Detection Methods for CVE-2025-7971
Indicators of Compromise
- Unexpected modifications to user or system environment variables referencing Studio 5000 paths
- Studio 5000 Logix Designer process crashes without corresponding legitimate cause
- Logix Designer loading executables or libraries from non-standard user-writable directories
- New or modified files in directories referenced by Studio 5000 environment variables
Detection Strategies
- Monitor process creation events where Logix Designer spawns child processes outside expected engineering workflows
- Audit environment variable changes on engineering workstations, particularly variables consumed by Rockwell Automation software
- Baseline legitimate file paths loaded by Studio 5000 and alert on deviations
- Correlate Logix Designer crashes with preceding environment variable modifications
Monitoring Recommendations
- Enable command-line and process telemetry on all engineering workstations running Studio 5000
- Log Windows Registry and user profile changes affecting environment variables
- Forward endpoint telemetry to a centralized SIEM for cross-host correlation of OT workstation activity
- Alert on unsigned or unexpected binaries loaded by Studio 5000 processes
How to Mitigate CVE-2025-7971
Immediate Actions Required
- Apply the security update referenced in Rockwell Automation Security Advisory SD1734 to all systems running Studio 5000 Logix Designer
- Restrict local access to engineering workstations to authorized control system engineers only
- Enforce least privilege on Windows accounts used to run Logix Designer
- Audit and remove unnecessary user-defined environment variables on affected workstations
Patch Information
Rockwell Automation has published mitigation guidance in Security Advisory SD1734. Customers should consult the advisory for the fixed version numbers applicable to their deployed release of Studio 5000 Logix Designer and upgrade accordingly.
Workarounds
- Segment engineering workstations from general-purpose IT networks using firewalls and jump hosts
- Disable interactive logon for non-engineering users on systems where Studio 5000 is installed
- Apply application allowlisting to restrict which binaries Logix Designer can load or execute
- Monitor and lock down modification of user and system environment variables through Group Policy
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
