CVE-2026-1734
📋 TL;DR
This vulnerability allows unauthorized remote access to the crontab endpoint in Zhong Bang CRMEB versions up to 5.6.3. Attackers can exploit this missing authorization flaw to potentially execute unauthorized actions or access sensitive functionality. All users running affected versions are at risk.
💻 Affected Systems
- Zhong Bang CRMEB
⚠️ Risk & Real-World Impact
Worst Case
Attackers could execute arbitrary cron jobs, manipulate scheduled tasks, access sensitive system functions, or potentially escalate privileges to compromise the entire application.
Likely Case
Unauthorized access to crontab functionality allowing manipulation of scheduled tasks, potentially disrupting business operations or enabling further exploitation.
If Mitigated
With proper authorization controls, the endpoint would reject unauthorized requests, preventing any exploitation of this vulnerability.
🎯 Exploit Status
Proof of concept available in public GitHub repository; exploit requires no authentication and minimal technical skill.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: None available
Restart Required: No
Instructions:
No official patch available. Consider upgrading to version 5.6.4 or later if released, or implement workarounds.
🔧 Temporary Workarounds
Restrict Access to Crontab Endpoint
allImplement access controls or firewall rules to restrict access to the vulnerable endpoint
# Example: Use web server configuration to block /api/controller/v1/CrontabController.php
# Apache: <Location "/crmeb/app/api/controller/v1/CrontabController.php">
# Order deny,allow
# Deny from all
# </Location>
# Nginx: location ~ /crmeb/app/api/controller/v1/CrontabController.php {
# deny all;
# }
Implement Authorization Middleware
allAdd proper authorization checks to the CrontabController.php file
# Modify crmeb/app/api/controller/v1/CrontabController.php
# Add authentication/authorization checks at the beginning of relevant methods
# Example PHP code: if (!$this->checkAuth()) {
# return json(['status' => 0, 'msg' => 'Unauthorized']);
# }
🧯 If You Can't Patch
- Implement network segmentation to isolate the CRMEB application from untrusted networks
- Deploy a web application firewall (WAF) with rules to detect and block unauthorized access to the crontab endpoint
🔍 How to Verify
Check if Vulnerable:
Check if your CRMEB version is 5.6.3 or earlier and test if unauthorized requests to the crontab endpoint are acceptedCheck Version:
Check CRMEB version in configuration files or admin panel; typically in crmeb/config/version.php or similarVerify Fix Applied:
Test that unauthorized requests to the crontab endpoint return proper authorization errors (e.g., 403 Forbidden)📡 Detection & Monitoring
Log Indicators:
- Unauthorized access attempts to /crmeb/app/api/controller/v1/CrontabController.php
- Unusual cron job executions or modifications
- Failed authorization attempts followed by successful crontab access
Network Indicators:
- HTTP requests to crontab endpoint without proper authentication headers or session tokens
- Unusual traffic patterns to the specific controller file
SIEM Query:
source="web_logs" AND (uri="/crmeb/app/api/controller/v1/CrontabController.php" OR uri LIKE "%CrontabController%") AND (response_code=200 OR response_code<400) AND NOT (user_agent="legitimate_bot" OR user="authenticated_user")