CVE-2018-5779
📋 TL;DR
This vulnerability allows unauthenticated attackers to execute arbitrary PHP code on Mitel conferencing systems by uploading malicious scripts. It affects Mitel Connect ONSITE R1711-PREM and earlier, and Mitel ST 14.2 GA28 and earlier. Attackers can achieve remote code execution within the application context.
💻 Affected Systems
- Mitel Connect ONSITE
- Mitel ST 14.2
📦 What is this software?
St14.2 by Mitel
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise allowing attackers to install backdoors, steal data, pivot to internal networks, or deploy ransomware.
Likely Case
Attackers gain initial foothold on the system, install web shells, and use the compromised system for further attacks.
If Mitigated
With proper network segmentation and monitoring, impact is limited to the affected system with quick detection and containment.
🎯 Exploit Status
The vulnerability requires specially crafted requests but is unauthenticated and leads directly to code execution.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Mitel Connect ONSITE: R1711-PREM SP1 and later; Mitel ST 14.2: GA29 and later
Vendor Advisory: https://www.mitel.com/support/security-advisories/mitel-product-security-advisory-18-0004
Restart Required: Yes
Instructions:
1. Download the appropriate patch from Mitel support portal. 2. Apply the patch following vendor instructions. 3. Restart the affected services or system. 4. Verify the patch is applied correctly.
🔧 Temporary Workarounds
Network Segmentation
allRestrict access to the conferencing component to trusted networks only
Web Application Firewall
allDeploy WAF rules to block malicious PHP file upload attempts
🧯 If You Can't Patch
- Isolate the system from internet access and restrict to internal trusted networks only
- Implement strict network monitoring and alerting for suspicious file upload activities
🔍 How to Verify
Check if Vulnerable:
Check system version against affected versions. If running Mitel Connect ONSITE R1711-PREM or earlier, or Mitel ST 14.2 GA28 or earlier, the system is vulnerable.Check Version:
Check via Mitel administration interface or consult system documentation for version checking commands.Verify Fix Applied:
Verify system version is updated to Mitel Connect ONSITE R1711-PREM SP1 or later, or Mitel ST 14.2 GA29 or later.📡 Detection & Monitoring
Log Indicators:
- Unusual PHP file creation in web directories
- Suspicious file upload requests to conferencing endpoints
- Unexpected process execution from web server context
Network Indicators:
- HTTP POST requests with PHP file uploads to conferencing URLs
- Outbound connections from web server to unexpected destinations
SIEM Query:
web.url:*conferencing* AND (web.method:POST AND web.uri:*php*) OR process.name:php AND parent.process:webserver