CVE-2021-0265
📋 TL;DR
CVE-2021-0265 is an unauthenticated remote code execution vulnerability in Juniper Networks AppFormix Agent's REST API. Attackers can execute arbitrary commands as root on affected systems when certain preconditions are met, granting full control. This affects AppFormix 3 versions prior to 3.1.22, 3.2.14, and 3.3.0.
💻 Affected Systems
- Juniper Networks AppFormix Agent
📦 What is this software?
Appformix by Juniper
Appformix by Juniper
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise with root-level access, allowing data theft, lateral movement, persistence installation, and service disruption.
Likely Case
Unauthenticated attackers gain root shell access on vulnerable AppFormix Agent hosts, enabling credential harvesting and network reconnaissance.
If Mitigated
With proper network segmentation and access controls, impact is limited to the AppFormix management network segment.
🎯 Exploit Status
CWE-78 indicates OS command injection, typically low complexity when unauthenticated access is available.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: AppFormix 3.1.22, 3.2.14, or 3.3.0
Vendor Advisory: https://kb.juniper.net/JSA11156
Restart Required: Yes
Instructions:
1. Download updated AppFormix version from Juniper support portal. 2. Backup current configuration. 3. Install updated version following Juniper documentation. 4. Restart AppFormix services.
🔧 Temporary Workarounds
Network Access Restriction
linuxRestrict network access to AppFormix Agent REST API to trusted management networks only.
iptables -A INPUT -p tcp --dport <appformix-port> -s <trusted-network> -j ACCEPT
iptables -A INPUT -p tcp --dport <appformix-port> -j DROP
🧯 If You Can't Patch
- Implement strict network segmentation to isolate AppFormix management network from untrusted networks
- Deploy host-based firewalls to restrict AppFormix Agent API access to authorized IP addresses only
🔍 How to Verify
Check if Vulnerable:
Check AppFormix version via web interface or CLI: appformix versionCheck Version:
appformix versionVerify Fix Applied:
Verify version is 3.1.22, 3.2.14, or 3.3.0 or higher📡 Detection & Monitoring
Log Indicators:
- Unusual REST API requests to AppFormix Agent
- Unexpected process execution as root from AppFormix context
- Authentication bypass attempts
Network Indicators:
- Unusual outbound connections from AppFormix hosts
- Command injection patterns in HTTP requests to AppFormix API
SIEM Query:
source="appformix" AND (event_type="api_request" AND (method="POST" OR method="PUT") AND (uri CONTAINS "/api/" OR uri CONTAINS "/rest/") AND (user_agent NOT IN ["trusted-agents"] OR src_ip NOT IN ["trusted-networks"]))