CVE-2022-24984
📋 TL;DR
This vulnerability allows remote unauthenticated attackers to upload executable files to websites using vulnerable JQueryForm.com forms, leading to remote code execution. Attackers can bypass client-side file extension checks by uploading files with extensions like .phtml or .php.bak. Any website using JQueryForm.com forms with file-upload capability enabled before February 5, 2022 is affected.
💻 Affected Systems
- JQueryForm.com forms
📦 What is this software?
Jqueryform by Jqueryform
⚠️ Risk & Real-World Impact
Worst Case
Complete server compromise allowing attackers to execute arbitrary code, steal data, install malware, or pivot to other systems.
Likely Case
Attackers upload web shells to gain persistent access, deface websites, or use servers for malicious activities.
If Mitigated
File uploads are blocked or properly validated, preventing malicious file execution.
🎯 Exploit Status
Simple file upload bypass with publicly available proof-of-concept. No authentication required.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Versions from 2022-02-05 onward
Vendor Advisory: https://JQueryForm.com
Restart Required: No
Instructions:
1. Update to JQueryForm.com version from February 5, 2022 or later. 2. Replace all vulnerable form implementations with updated versions. 3. Test file upload functionality after update.
🔧 Temporary Workarounds
Server-side file validation
allImplement server-side validation of file extensions and content types
Implement PHP validation: $allowed_extensions = ['jpg', 'png', 'pdf']; $file_extension = strtolower(pathinfo($_FILES['file']['name'], PATHINFO_EXTENSION)); if (!in_array($file_extension, $allowed_extensions)) { die('Invalid file type'); }
Disable file upload capability
allTemporarily disable file upload functionality in vulnerable forms
Remove or comment out file upload fields in form configuration
🧯 If You Can't Patch
- Implement web application firewall (WAF) rules to block suspicious file uploads
- Restrict upload directory permissions and disable script execution in upload directories
🔍 How to Verify
Check if Vulnerable:
Check if your website uses JQueryForm.com forms with file upload enabled and if implementation date is before February 5, 2022.Check Version:
Check form implementation date in source code or contact JQueryForm.com for version information.Verify Fix Applied:
Test file upload functionality with malicious extensions (.phtml, .php.bak) - they should be rejected with server-side validation.📡 Detection & Monitoring
Log Indicators:
- File upload attempts with .phtml, .php.bak, or other executable extensions
- Unusual POST requests to upload endpoints
- Files with executable extensions appearing in upload directories
Network Indicators:
- POST requests with file uploads to form endpoints
- Subsequent requests to uploaded executable files
SIEM Query:
source="web_logs" AND (uri_path="*upload*" OR method="POST") AND (user_agent="*curl*" OR user_agent="*wget*" OR file_extension="*.phtml" OR file_extension="*.php.bak")