CVE-2025-65783 Overview
An arbitrary file upload vulnerability exists in the /utils/uploadFile component of Hubert Imoveis e Administracao Ltda Hub v2.0 1.27.3. This vulnerability allows attackers to execute arbitrary code on the target system by uploading a specially crafted PDF file. The file upload mechanism fails to properly validate uploaded file contents, enabling threat actors to bypass security controls and achieve remote code execution.
Critical Impact
Attackers can achieve remote code execution by exploiting the unrestricted file upload functionality, potentially leading to complete system compromise, data exfiltration, and lateral movement within the network.
Affected Products
- Hubert Imoveis e Administracao Ltda Hub v2.0
- Hub version 1.27.3
- /utils/uploadFile component
Discovery Timeline
- January 13, 2026 - CVE-2025-65783 published to NVD
- January 13, 2026 - Last updated in NVD database
Technical Details for CVE-2025-65783
Vulnerability Analysis
This arbitrary file upload vulnerability represents a significant security risk common in web applications that handle user-submitted files without adequate validation. The /utils/uploadFile endpoint in Hub v2.0 1.27.3 accepts file uploads but fails to properly validate the content type and actual file structure of uploaded documents.
The vulnerability specifically involves the ability to upload malicious content disguised as a PDF file. When the server processes the uploaded file, the embedded malicious payload can be executed, granting attackers the ability to run arbitrary commands on the underlying system. This type of vulnerability is particularly dangerous because it can be exploited remotely without requiring prior authentication in some configurations.
Successful exploitation could allow an attacker to install backdoors, steal sensitive data, modify system configurations, or use the compromised server as a pivot point for further attacks within the network infrastructure.
Root Cause
The root cause of this vulnerability is insufficient input validation and file content verification in the upload handling mechanism. The /utils/uploadFile component relies on client-supplied file extensions or MIME types rather than performing deep content inspection to verify that uploaded files are legitimate PDF documents. This allows attackers to craft malicious files with PDF extensions that contain executable code or scripts.
Attack Vector
The attack is conducted through the web interface by submitting a specially crafted file to the /utils/uploadFile endpoint. The attacker creates a malicious file containing code execution payloads and disguises it as a legitimate PDF document. When the file is processed or accessed by the server, the malicious code is executed with the privileges of the web server process.
The vulnerability mechanism involves bypassing file type validation by crafting a file that appears to be a PDF to surface-level checks but contains embedded executable content. Attackers may leverage polyglot files or exploit server-side file processing to trigger code execution. For detailed technical analysis, refer to the GitHub CVE-2025-65783 Research repository.
Detection Methods for CVE-2025-65783
Indicators of Compromise
- Unusual file uploads to the /utils/uploadFile endpoint with suspicious file contents or malformed PDF structures
- Web server processes spawning unexpected child processes or making outbound network connections
- Presence of newly created files in web-accessible directories with executable permissions
- Log entries showing repeated file upload attempts with varying payloads targeting the vulnerable endpoint
Detection Strategies
- Implement web application firewall (WAF) rules to inspect file upload requests for known malicious patterns and polyglot file signatures
- Deploy file integrity monitoring on upload directories to detect unauthorized file modifications or additions
- Configure intrusion detection systems (IDS) to alert on suspicious process execution patterns originating from web server contexts
- Monitor HTTP request logs for anomalous activity targeting the /utils/uploadFile endpoint
Monitoring Recommendations
- Enable verbose logging for all file upload operations including source IP, file metadata, and processing outcomes
- Implement real-time alerting for file uploads that fail content validation or exhibit characteristics of known attack patterns
- Establish baseline network behavior for web servers and alert on deviations indicating potential command and control activity
- Review web server access logs regularly for patterns consistent with vulnerability scanning or exploitation attempts
How to Mitigate CVE-2025-65783
Immediate Actions Required
- Restrict access to the /utils/uploadFile endpoint to authenticated and authorized users only
- Implement a web application firewall to block malicious file upload attempts while awaiting a vendor patch
- Consider temporarily disabling the file upload functionality if it is not business-critical
- Audit existing uploaded files for signs of malicious content and remove any suspicious files
Patch Information
Contact Hubert Imoveis e Administracao Ltda for information regarding security patches for Hub v2.0 1.27.3. Monitor the Hub Homepage and Hubert Security Resource for security advisories and updates. Additional vulnerability research details are available at the GitHub CVE-2025-65783 Research repository.
Workarounds
- Implement strict file type validation by examining file magic bytes rather than relying on file extensions or client-provided MIME types
- Configure the web server to prevent execution of uploaded files by placing upload directories outside the web root or removing execute permissions
- Deploy content security policies that restrict the types of files that can be uploaded and processed by the application
- Use sandboxed file processing environments to safely analyze uploaded content before making it accessible
# Configuration example - Restrict upload directory permissions
chmod 640 /path/to/upload/directory
chown www-data:www-data /path/to/upload/directory
# Disable script execution in upload directory (Apache example)
# Add to .htaccess or virtual host configuration
# Options -ExecCGI
# RemoveHandler .php .phtml .php3 .php4 .php5 .phps
# ForceType application/octet-stream
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
