CVE-2025-61863: Fujielectric Monitouch V-SFT Vulnerability

CVE-2025-61863 Overview

CVE-2025-61863 is an out-of-bounds read vulnerability in VS6ComFile!CSaveData::delete_mem within Fuji Electric V-SFT v6.2.7.0 and earlier. V-SFT is configuration software used to design screens for Fuji Electric MONITOUCH human-machine interface (HMI) panels deployed in industrial control environments. Opening a specially crafted V-SFT project file triggers the flaw, which is tracked as [CWE-125]. Successful exploitation may lead to information disclosure, abnormal process termination (ABEND), and arbitrary code execution on the engineering workstation. The issue was published to the National Vulnerability Database (NVD) on 2025-10-10 and coordinated through JPCERT/CC.

Critical Impact
A crafted V-SFT file can leak process memory, crash the application, or execute arbitrary code on engineering workstations that manage industrial HMI deployments.

Affected Products

Fuji Electric MONITOUCH V-SFT v6.2.7.0
Fuji Electric MONITOUCH V-SFT versions prior to v6.2.7.0
Engineering workstations running the vulnerable VS6ComFile component

Discovery Timeline

2025-10-10 - CVE-2025-61863 published to NVD
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2025-61863

Vulnerability Analysis

The flaw resides in the CSaveData::delete_mem function exported by VS6ComFile, a component responsible for parsing and cleaning up serialized project data in V-SFT. When the parser processes a malformed V-SFT file, it dereferences memory beyond the bounds of an allocated buffer. The read primitive can expose adjacent heap contents, corrupt program state, or, depending on layout, redirect control flow. Because V-SFT files are the native project format for MONITOUCH HMI design, engineers routinely open them from email, shared drives, or vendor deliverables — creating a realistic path for attackers to reach the parser.

Root Cause

The root cause is missing or incorrect bounds validation on a size or offset field consumed by CSaveData::delete_mem. The routine assumes structural fields inside the V-SFT container are trustworthy and does not verify them against the actual allocation length before reading. This classifies the defect under [CWE-125] Out-of-bounds Read. The consequence is undefined behavior when the crafted offset exceeds the buffer, ranging from a leaked pointer to a controlled crash suitable for exploitation chaining.

Attack Vector

Exploitation requires local access and user interaction. An attacker delivers a crafted .V* project file — typically through phishing, a compromised supplier, or a shared engineering repository. When an operator opens the file in V-SFT, VS6ComFile parses it and reaches the vulnerable routine. No authentication is required against the target application. The attacker gains code execution in the security context of the user running V-SFT, which in operational technology (OT) environments is often a privileged engineering account with network reach to programmable logic controllers (PLCs) and HMI devices.

No public proof-of-concept or exploit code has been published at the time of writing. Technical specifics are described in the JVN Security Advisory.

Detection Methods for CVE-2025-61863

Indicators of Compromise

Unexpected crashes or ABEND events in the V-SFT process (V-SFT.exe) with faulting module VS6ComFile.dll.
Windows Error Reporting (WER) entries referencing CSaveData::delete_mem or access violations inside VS6ComFile.
V-SFT project files arriving from external senders or unusual locations, particularly with malformed headers or abnormal file sizes.
Child processes spawned by V-SFT.exe such as cmd.exe, powershell.exe, or rundll32.exe shortly after a file open.

Detection Strategies

Monitor endpoint telemetry on engineering workstations for V-SFT.exe crashes and correlate with the file most recently opened.
Deploy YARA or file-inspection rules on mail and file-share gateways to flag V-SFT project files originating outside the trusted engineering supply chain.
Baseline the normal process tree of V-SFT.exe and alert on deviations that indicate post-exploitation activity.

Monitoring Recommendations

Enable and forward Windows application and WER logs from OT engineering workstations to a centralized SIEM.
Track file-write and file-open events for *.V6* project files across shared engineering repositories.
Audit outbound network connections from engineering hosts, which normally communicate only with HMI panels and PLCs on segmented networks.

How to Mitigate CVE-2025-61863

Immediate Actions Required

Inventory all workstations running Fuji Electric V-SFT and identify installations at or below v6.2.7.0.
Restrict V-SFT project file handling to trusted internal sources until patched; block inbound project files at the mail gateway.
Enforce least privilege on engineering accounts so that a compromised V-SFT process cannot pivot to domain resources.
Isolate engineering workstations from general-purpose IT networks using firewall segmentation aligned with IEC 62443 zones and conduits.

Patch Information

Fuji Electric distributes fixed V-SFT builds through its official download portal. Obtain the updated release from the Fuji Electric MONITOUCH Download site and follow the vendor upgrade procedure. Refer to the JVN Security Advisory for coordinated disclosure details and the confirmed fixed version.

Workarounds

Do not open V-SFT project files received from untrusted or unverified sources.
Open suspicious files inside an isolated virtual machine that has no network path to production OT assets.
Apply application allowlisting so that V-SFT.exe cannot launch unexpected child processes such as script interpreters.
Enable Windows exploit mitigations (DEP, ASLR, CFG) on engineering workstations to raise the cost of code execution.

bash

# Example: verify installed V-SFT version on Windows via PowerShell
Get-ItemProperty "HKLM:\SOFTWARE\WOW6432Node\Microsoft\Windows\CurrentVersion\Uninstall\*" |
  Where-Object { $_.DisplayName -like "*V-SFT*" } |
  Select-Object DisplayName, DisplayVersion, Publisher