CVE-2022-50911: Bitrix24 RCE Vulnerability

CVE-2022-50911 Overview

CVE-2022-50911 is an authenticated remote code execution vulnerability affecting Bitrix24, a popular business collaboration platform. The vulnerability allows logged-in attackers to execute arbitrary system commands through the PHP command line admin interface. By sending crafted POST requests to administrative endpoints, attackers can execute code with the web application's privileges, potentially leading to full system compromise.

Critical Impact

Authenticated attackers can achieve remote code execution on affected Bitrix24 installations, enabling arbitrary command execution with web application privileges and potential full server compromise.

Affected Products

• Bitrix24 (versions with vulnerable PHP command line admin interface)

Discovery Timeline

• 2026-01-13 - CVE CVE-2022-50911 published to NVD
• 2026-01-13 - Last updated in NVD database

Technical Details for CVE-2022-50911

Vulnerability Analysis

This vulnerability is classified under CWE-862 (Missing Authorization), indicating that the PHP command line admin interface fails to properly enforce authorization controls. The flaw allows authenticated users to bypass intended security restrictions and execute system commands that should be restricted to highly privileged administrators only.

The attack is network-based and requires low complexity to exploit. An attacker needs only basic authentication credentials (low privileges) to leverage this vulnerability. No user interaction is required, making it particularly dangerous in environments where lower-privileged users have access to the Bitrix24 administration panel.

Successful exploitation results in high impact across confidentiality, integrity, and availability. Attackers can read sensitive data, modify system configurations, and potentially disrupt service availability by executing malicious commands on the underlying server.

Root Cause

The root cause of CVE-2022-50911 lies in missing authorization checks within the PHP command line admin interface. The application fails to properly validate whether authenticated users have sufficient privileges to execute system commands through this administrative feature. This missing authorization control allows any authenticated user to access functionality that should be restricted to system administrators.

Attack Vector

The attack is conducted over the network and targets the Bitrix24 administrative interface. An attacker with valid user credentials can:

1. Authenticate to the Bitrix24 application with any valid account
2. Navigate to or directly access the PHP command line admin interface endpoint
3. Craft malicious POST requests containing system commands
4. Submit the requests to execute arbitrary commands on the server

The commands execute with the privileges of the web application process, which typically runs as www-data, apache, or a similar service account. This level of access is often sufficient for attackers to escalate privileges, exfiltrate data, establish persistence, or pivot to other systems on the network.

For technical details and proof-of-concept information, refer to the Exploit-DB #50898 entry and the VulnCheck Bitrix RCE Advisory.

Detection Methods for CVE-2022-50911

Indicators of Compromise

• Unusual POST requests to Bitrix24 administrative endpoints containing shell commands or system utilities (e.g., whoami, id, cat, wget, curl)
• Unexpected process spawning from the web server process (Apache, Nginx, PHP-FPM)
• Web server logs showing repeated access to PHP command line interface endpoints by non-administrator accounts
• Anomalous outbound network connections originating from the web application server

Detection Strategies

• Implement web application firewall (WAF) rules to detect and block requests containing OS command injection patterns targeting Bitrix24 administrative endpoints
• Configure SIEM rules to alert on authentication events followed by access to sensitive administrative interfaces
• Deploy file integrity monitoring to detect unauthorized modifications to Bitrix24 configuration files or web directories
• Monitor for creation of new web shells or suspicious PHP files in the Bitrix24 installation directory

Monitoring Recommendations

• Enable detailed logging for all Bitrix24 administrative interface access, including source IP, authenticated user, and request parameters
• Implement network traffic analysis to identify command-and-control communications originating from web servers
• Configure endpoint detection and response (EDR) solutions to monitor process chains where web server processes spawn shell interpreters
• Regularly audit user accounts with access to Bitrix24 administrative features and review their activity logs

How to Mitigate CVE-2022-50911

Immediate Actions Required

• Restrict access to the Bitrix24 PHP command line admin interface to only trusted administrator accounts
• Implement network-level access controls (IP whitelisting) for administrative endpoints
• Review and audit all user accounts with access to Bitrix24 administrative functions
• Consider temporarily disabling the PHP command line admin interface until a patch is applied
• Deploy web application firewall rules to block command injection attempts

Patch Information

Review the Bitrix24 Desktop Application page and official Bitrix24 security announcements for updated versions that address this vulnerability. Contact Bitrix24 support for guidance on obtaining and applying security patches for your deployment.

For additional technical details, consult the VulnCheck Bitrix RCE Advisory.

Workarounds

• Disable or remove access to the PHP command line admin interface if not required for operations
• Implement strict role-based access controls ensuring only verified system administrators can access administrative features
• Place Bitrix24 administrative interfaces behind VPN or IP-restricted access controls
• Enable multi-factor authentication for all administrative accounts
• Configure the web server to log all POST requests to administrative endpoints for forensic analysis

# Example: Restrict access to admin interface via Apache configuration
<Location "/bitrix/admin/">
    Require ip 10.0.0.0/8
    Require ip 192.168.0.0/16
    # Deny all other access
    Require all denied
</Location>