CVE-2021-1487
📋 TL;DR
This vulnerability allows authenticated remote attackers to execute arbitrary commands on Cisco Prime Infrastructure and EPN Manager systems via crafted HTTP requests to the web management interface. Successful exploitation could lead to complete system compromise, data theft, and disruption of managed network devices. Only authenticated users can exploit this vulnerability.
💻 Affected Systems
- Cisco Prime Infrastructure
- Cisco Evolved Programmable Network Manager
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete system takeover allowing attacker to execute arbitrary commands, steal sensitive data including device credentials, push malicious configurations to managed devices, and cause widespread network disruption.
Likely Case
Attacker gains command execution with non-root privileges, accesses sensitive configuration data, and potentially escalates privileges to fully compromise the management system.
If Mitigated
With proper network segmentation and access controls, impact limited to isolated management network segment with no access to production systems.
🎯 Exploit Status
Exploitation requires authentication but is straightforward once authenticated. No public exploit code available but trivial to weaponize.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Prime Infrastructure: 3.7.3 Update, 3.8.1 Update, 3.9 Update, 3.10 Update; EPN Manager: 5.0.1 Update
Vendor Advisory: https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-pi-epnm-cmd-inj-YU5e6tB3
Restart Required: Yes
Instructions:
1. Download appropriate patch from Cisco Software Center. 2. Backup current configuration. 3. Apply patch following Cisco documentation. 4. Restart affected services or system. 5. Verify patch installation.
🔧 Temporary Workarounds
Restrict Web Interface Access
linuxLimit access to web management interface to trusted IP addresses only using firewall rules.
iptables -A INPUT -p tcp --dport 443 -s trusted_ip_range -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -j DROP
Disable Unused Features
allDisable any unnecessary web interface features or APIs that may be vulnerable.
🧯 If You Can't Patch
- Implement strict network segmentation to isolate management systems from production networks
- Enforce strong authentication policies and multi-factor authentication for all management interfaces
🔍 How to Verify
Check if Vulnerable:
Check current version against affected versions list. Run: show version command in CLI or check web interface version.Check Version:
show versionVerify Fix Applied:
Verify installed version matches patched versions. Check patch status in system logs and verify web interface responds normally.📡 Detection & Monitoring
Log Indicators:
- Unusual HTTP POST requests to management interface
- Command execution patterns in system logs
- Authentication attempts from unusual sources
Network Indicators:
- HTTP requests with command injection patterns to /webui/ endpoints
- Unusual outbound connections from management system
SIEM Query:
source="cisco_prime" AND (http_method="POST" AND (uri="*webui*" OR uri="*api*")) AND (http_user_agent="*curl*" OR http_user_agent="*wget*" OR http_user_agent="*python*"))