CVE-2024-0712: Byzoro Smart S150 Auth Bypass Vulnerability

CVE-2024-0712 Overview

A critical improper access control vulnerability has been identified in the Byzoro Smart S150 Management Platform V31R02B15. This vulnerability affects an unknown function within the file /useratte/inc/userattea.php, allowing remote attackers to bypass access controls and potentially compromise the system. The exploit has been publicly disclosed, and the vendor was contacted but did not respond to the disclosure.

Critical Impact

This vulnerability allows unauthenticated remote attackers to bypass access controls on the Byzoro Smart S150 Management Platform, potentially leading to complete system compromise with unauthorized access to confidential data, system modification capabilities, and service disruption.

Affected Products

• Byzoro Smart S150 Firmware version 31R02B15
• Byzoro Smart S150 hardware device
• Byzoro Smart S150 Management Platform V31R02B15

Discovery Timeline

• 2024-01-19 - CVE-2024-0712 published to NVD
• 2024-11-21 - Last updated in NVD database

Technical Details for CVE-2024-0712

Vulnerability Analysis

This vulnerability stems from improper access control implementation (CWE-284) in the Byzoro Smart S150 Management Platform's user attendance module. The affected endpoint /useratte/inc/userattea.php fails to properly validate user authorization before processing requests, allowing attackers to access restricted functionality without proper authentication.

The vulnerability is remotely exploitable without requiring user interaction or prior authentication. A successful attack could result in unauthorized access to sensitive management functions, modification of system configurations, and potential denial of service to legitimate administrators.

Root Cause

The root cause of CVE-2024-0712 is the lack of proper authorization checks in the userattea.php file. The application fails to verify whether incoming requests originate from authenticated and authorized users before executing sensitive operations. This broken access control pattern allows any network-accessible attacker to interact with the management platform's backend functionality.

Attack Vector

The attack can be launched remotely over the network. An attacker with network access to the Byzoro Smart S150 Management Platform can send crafted requests directly to the vulnerable /useratte/inc/userattea.php endpoint. Since no authentication is required, attackers can manipulate parameters to bypass intended access restrictions and execute unauthorized operations.

The vulnerability was publicly disclosed via a GitHub PoC Repository, and additional technical details are available through VulDB #251538.

Detection Methods for CVE-2024-0712

Indicators of Compromise

• Unexpected HTTP requests to /useratte/inc/userattea.php from untrusted IP addresses
• Unusual access patterns to user attendance management functions without valid session tokens
• Web server logs showing repeated requests to the vulnerable endpoint from external sources
• Authentication bypass attempts or requests lacking proper authorization headers

Detection Strategies

• Configure web application firewall (WAF) rules to monitor and alert on requests to /useratte/inc/userattea.php from unauthenticated sources
• Implement intrusion detection signatures for anomalous access patterns targeting the user attendance module
• Deploy network monitoring to detect unauthorized access attempts to the management platform interface
• Enable verbose logging on the Byzoro Smart S150 device to capture all requests to PHP endpoints

Monitoring Recommendations

• Establish baseline traffic patterns to the management platform and alert on deviations
• Monitor for requests originating from unexpected geographic locations or IP ranges
• Set up real-time alerts for any access to the vulnerable PHP file without corresponding authentication events
• Review access logs regularly for signs of reconnaissance or exploitation attempts

How to Mitigate CVE-2024-0712

Immediate Actions Required

• Restrict network access to the Byzoro Smart S150 Management Platform to trusted IP addresses only using firewall rules
• Place the management interface behind a VPN or other network segmentation controls
• Implement additional authentication layers (such as HTTP Basic Auth) at the web server level for the vulnerable endpoint
• Monitor all access to the device until a vendor patch becomes available

Patch Information

As of the last modification date, the vendor (Byzoro) has not responded to disclosure attempts and no official patch is available. Organizations using affected devices should implement the workarounds listed below and monitor vendor communications for future security updates. Consider contacting Byzoro support directly to request a security patch or firmware update addressing CVE-2024-0712.

Workarounds

• Implement network-level access controls to restrict management platform access to authorized administrator IP addresses only
• Deploy a reverse proxy with authentication in front of the management interface to enforce access controls
• If feasible, disable or block access to /useratte/inc/userattea.php until a patch is available
• Consider taking the management platform offline and managing devices through alternative secure methods if possible

# Example: Block external access to the vulnerable endpoint using iptables
# Allow only trusted management network (example: 10.0.0.0/24)
iptables -A INPUT -p tcp --dport 80 -s 10.0.0.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -s 10.0.0.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -j DROP
iptables -A INPUT -p tcp --dport 443 -j DROP