V-Sft — CraftedSignal Threat Feed

V-SFT Stack-Based Buffer Overflow Vulnerability (CVE-2026-32928)

hello@craftedsignal.io — Wed, 01 Apr 2026 23:17:03 +0000

V-SFT versions 6.2.10.0 and earlier are vulnerable to a stack-based buffer overflow (CVE-2026-32928) located in the VS6ComFile!CSaveData::_conv_AnimationItem function. This vulnerability is triggered when the software processes a specially crafted V7 file. Successful exploitation of this vulnerability can lead to arbitrary code execution within the context of the application. Given the potential for complete system compromise, organizations using affected versions of V-SFT should take immediate steps to mitigate this risk. This vulnerability was reported by JPCERT/CC.

Attack Chain

Attacker identifies a target using a vulnerable version of V-SFT (<= 6.2.10.0).
Attacker crafts a malicious V7 file designed to trigger the buffer overflow in the VS6ComFile!CSaveData::_conv_AnimationItem function.
The attacker delivers the malicious V7 file to the target, potentially through social engineering or other means.
The target user opens the malicious V7 file using the vulnerable V-SFT software.
The VS6ComFile!CSaveData::_conv_AnimationItem function processes the V7 file, copying data into a fixed-size buffer on the stack.
The crafted V7 file contains data exceeding the buffer’s capacity, causing a buffer overflow.
The overflow overwrites adjacent stack memory, including the return address.
When the _conv_AnimationItem function returns, execution is redirected to an attacker-controlled address, allowing arbitrary code execution.

Impact

Successful exploitation of CVE-2026-32928 allows an attacker to execute arbitrary code on the affected system. This could lead to complete system compromise, data theft, or denial of service. The vulnerability affects any system running V-SFT versions 6.2.10.0 and prior. The severity is rated as high with a CVSS v3.1 score of 7.8.

Recommendation

Apply the patch or upgrade to a non-vulnerable version of V-SFT (later than 6.2.10.0) as provided by the vendor.
Monitor process creation events for V-SFT processes spawning child processes or executing unusual commands, using the provided Sigma rule.
Implement file integrity monitoring for the V-SFT executable and associated libraries to detect unauthorized modifications.
Educate users about the risks of opening files from untrusted sources to mitigate social engineering attacks.

V-SFT Out-of-Bounds Read Vulnerability (CVE-2026-32929)

hello@craftedsignal.io — Wed, 01 Apr 2026 23:17:03 +0000

CVE-2026-32929 is an out-of-bounds read vulnerability affecting V-SFT versions 6.2.10.0 and prior. The vulnerability exists within the VS6ComFile!get_macro_mem_COM function. An attacker can exploit this vulnerability by crafting a malicious V7 file. When a user opens the crafted V7 file with a vulnerable version of V-SFT, the out-of-bounds read can be triggered, leading to potential information disclosure. This vulnerability was disclosed on April 1, 2026, and poses a risk to users who rely on V-SFT software for industrial automation and control systems. Organizations should assess their exposure to this vulnerability and take appropriate mitigation steps, including updating to a patched version of V-SFT.

Attack Chain

Attacker identifies a target using V-SFT versions 6.2.10.0 or prior.
Attacker crafts a malicious V7 file specifically designed to trigger the out-of-bounds read in VS6ComFile!get_macro_mem_COM.
Attacker delivers the crafted V7 file to the target, possibly through social engineering or other means.
The target user opens the malicious V7 file using the vulnerable V-SFT software.
V-SFT attempts to parse the crafted V7 file, triggering the VS6ComFile!get_macro_mem_COM function.
Due to the malformed structure of the crafted V7 file, the get_macro_mem_COM function attempts to read data beyond the allocated buffer.
The out-of-bounds read occurs, potentially disclosing sensitive information from the V-SFT process memory.
The attacker may be able to leverage the disclosed information to further compromise the system or network.

Impact

Successful exploitation of CVE-2026-32929 can lead to information disclosure. An attacker who successfully exploits this vulnerability may be able to read sensitive data from the memory of the V-SFT process. The disclosed information could potentially include configuration settings, credentials, or other sensitive data that could be used to further compromise the affected system. While the NVD does not yet contain scoring data, JPCERT/CC assigned a base score of 7.8 HIGH.

Recommendation

Upgrade V-SFT to a version that patches CVE-2026-32929 to remediate the vulnerability.
Deploy the Sigma rule “Detect V-SFT V7 File Opening” to detect attempts to open V7 files using the vulnerable software.
Monitor systems running V-SFT for unexpected behavior or crashes, which could indicate exploitation attempts.
Educate users about the risks of opening files from untrusted sources to prevent social engineering attacks.

V-SFT v6.2.10.0 Stack-Based Buffer Overflow (CVE-2026-32925)

hello@craftedsignal.io — Wed, 01 Apr 2026 23:17:02 +0000

V-SFT versions 6.2.10.0 and earlier are susceptible to a critical stack-based buffer overflow vulnerability identified as CVE-2026-32925. This flaw resides within the VS6ComFile!CV7BaseMap::WriteV7DataToRom function. The vulnerability is triggered when the software processes a specially crafted V7 file. A successful exploit could allow an attacker to execute arbitrary code within the context of the application. This poses a significant risk to systems utilizing affected versions of V-SFT, as it could lead to complete system compromise. The vulnerability was reported to JPCERT/CC and assigned CWE-121, highlighting the classic stack-based buffer overflow nature of the issue.

Attack Chain

The attacker crafts a malicious V7 file designed to exploit the buffer overflow in VS6ComFile!CV7BaseMap::WriteV7DataToRom.
The user opens the malicious V7 file using a vulnerable version of V-SFT (6.2.10.0 or prior).
V-SFT attempts to parse the V7 file, specifically calling the CV7BaseMap::WriteV7DataToRom function.
During the WriteV7DataToRom function execution, the crafted V7 file provides input that exceeds the buffer size allocated on the stack.
The excessive input overwrites adjacent memory locations on the stack, including the return address.
Upon completion of the WriteV7DataToRom function, control is transferred to the overwritten return address.
The attacker redirects code execution to a location containing malicious code injected into the process memory.
The injected code executes with the privileges of the V-SFT application, potentially leading to complete system compromise.

Impact

Successful exploitation of CVE-2026-32925 allows an attacker to execute arbitrary code on systems running vulnerable versions of V-SFT (6.2.10.0 and prior). This could result in complete system compromise, data theft, or denial of service. The exact number of potential victims is unknown, but the severity is high due to the potential for arbitrary code execution.

Recommendation

Apply the patch or upgrade to a non-vulnerable version of V-SFT as provided by the vendor (Fujielectric). Refer to the vendor advisory (https://felib.fujielectric.co.jp/en/M10010/M20060/document_detail/5d9dd71d-9494-41a4-aa5c-8e6b8b21066b?region=en-glb).
Monitor process creation events for V-SFT spawning unusual child processes, which might indicate successful code execution. Utilize the Sigma rule “Detect Suspicious V-SFT Child Processes” to identify such behavior.
Implement file integrity monitoring for the V-SFT executable and related libraries to detect unauthorized modifications.