CVE-2021-36982
📋 TL;DR
This vulnerability allows remote attackers to execute arbitrary operating system commands on MONITORAPP Application Insight Web Application Firewall (AIWAF) devices. Attackers can exploit missing input validation in an HTTP request parameter to achieve command injection. Organizations using affected AIWAF devices with Manager 2.1.0 before version B115 are vulnerable.
💻 Affected Systems
- MONITORAPP Application Insight Web Application Firewall (AIWAF)
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete compromise of the AIWAF device leading to full system control, lateral movement to internal networks, data exfiltration, and persistent backdoor installation.
Likely Case
Unauthorized command execution on the AIWAF device, potentially allowing configuration changes, log manipulation, or deployment of additional malware.
If Mitigated
Limited impact due to network segmentation, proper input validation, and restricted user permissions on the device.
🎯 Exploit Status
FireEye disclosed technical details including exploitation vectors. The vulnerability requires sending a specially crafted HTTP request to the vulnerable parameter.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: B115 or later
Vendor Advisory: https://github.com/monitorapp-aicc/report/wiki/CVE-2021-36982
Restart Required: Yes
Instructions:
1. Log into AIWAF management interface. 2. Check current version. 3. If below B115, download and apply patch from MONITORAPP. 4. Restart the AIWAF device. 5. Verify version is B115 or later.
🔧 Temporary Workarounds
Input Validation Filter
allImplement strict input validation for HTTP request parameters on the AIWAF device
Configure AIWAF rules to reject requests containing shell metacharacters in vulnerable parameter
Network Segmentation
allRestrict access to AIWAF management interface
Configure firewall rules to allow only trusted IPs to access AIWAF management interface
🧯 If You Can't Patch
- Isolate AIWAF management interface behind firewall with strict IP whitelisting
- Implement network monitoring for suspicious HTTP requests containing shell metacharacters
🔍 How to Verify
Check if Vulnerable:
Check AIWAF version via management interface. If Manager version is 2.1.0 and build number is below B115, the device is vulnerable.Check Version:
Check via AIWAF web interface: System > About or equivalent menuVerify Fix Applied:
Verify version shows B115 or later in management interface. Test with safe command injection payloads to confirm input validation is working.📡 Detection & Monitoring
Log Indicators:
- HTTP requests containing shell metacharacters (;, |, &, $, `) in vulnerable parameter
- Unusual command execution in system logs
- Failed authentication attempts followed by command injection patterns
Network Indicators:
- HTTP POST requests to AIWAF management interface with suspicious parameter values
- Unexpected outbound connections from AIWAF device
SIEM Query:
source="aiwaf" AND (http.uri="*vulnerable-endpoint*" AND http.param="*[;|&`$]*")🔗 References
- https://github.com/fireeye/Vulnerability-Disclosures/blob/master/FEYE-2021-0022/FEYE-2021-0022.md
- https://github.com/monitorapp-aicc/report/wiki/CVE-2021-36982
- https://www.monitorapp.com/waf/
- https://github.com/fireeye/Vulnerability-Disclosures/blob/master/FEYE-2021-0022/FEYE-2021-0022.md
- https://github.com/monitorapp-aicc/report/wiki/CVE-2021-36982
- https://www.monitorapp.com/waf/
