CVE-2024-24091
📋 TL;DR
This vulnerability allows remote attackers to execute arbitrary operating system commands on Yealink Meeting Servers through the file upload interface. Attackers can potentially gain full control of affected systems. Organizations running Yealink Meeting Server versions before 26.0.0.66 are affected.
💻 Affected Systems
- Yealink Meeting Server
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise allowing attackers to execute arbitrary commands with root/system privileges, install malware, exfiltrate data, and pivot to other network resources.
Likely Case
Remote code execution leading to unauthorized access, data theft, and potential deployment of ransomware or other malicious payloads.
If Mitigated
Limited impact if proper network segmentation, strict access controls, and monitoring are in place, though the vulnerability still presents significant risk.
🎯 Exploit Status
Command injection vulnerabilities typically have low exploitation complexity once the attack vector is identified. The advisory suggests authentication may be required.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 26.0.0.66 and later
Vendor Advisory: https://www.yealink.com/en/trust-center/security-advisories/2f2b990211c440cf
Restart Required: Yes
Instructions:
1. Download Yealink Meeting Server version 26.0.0.66 or later from Yealink's official website. 2. Backup current configuration and data. 3. Install the update following Yealink's upgrade documentation. 4. Restart the server to apply changes. 5. Verify the update was successful.
🔧 Temporary Workarounds
Restrict File Upload Access
linuxImplement network-level restrictions to limit access to the file upload interface to trusted IP addresses only.
iptables -A INPUT -p tcp --dport [MEETING_SERVER_PORT] -s [TRUSTED_IP] -j ACCEPT
iptables -A INPUT -p tcp --dport [MEETING_SERVER_PORT] -j DROP
Disable Unnecessary Features
allTemporarily disable the file upload functionality if not required for business operations.
🧯 If You Can't Patch
- Implement strict network segmentation to isolate Yealink Meeting Server from critical systems
- Deploy web application firewall (WAF) rules to block command injection patterns and restrict file uploads
🔍 How to Verify
Check if Vulnerable:
Check the Yealink Meeting Server version via the web admin interface or SSH into the server and check the installed version.Check Version:
ssh admin@[server_ip] 'cat /opt/yealink/meeting/version.txt' or check via web admin interfaceVerify Fix Applied:
Verify the server version is 26.0.0.66 or higher and test the file upload functionality with safe test files.📡 Detection & Monitoring
Log Indicators:
- Unusual file upload activity
- Suspicious command execution patterns in system logs
- Multiple failed upload attempts followed by successful upload
Network Indicators:
- Unusual outbound connections from the meeting server
- Traffic patterns indicating command and control communication
SIEM Query:
source="yealink-meeting-server" AND (event="file_upload" AND size>1000000) OR (process="bash" OR process="sh" AND parent_process="meeting-server")