CVE-2021-1264
📋 TL;DR
This vulnerability allows authenticated remote attackers to execute arbitrary CLI commands on devices managed by Cisco DNA Center through command injection in the Command Runner tool. It affects organizations using Cisco DNA Center for network management. Attackers can compromise managed network devices if they have valid credentials.
💻 Affected Systems
- Cisco DNA Center
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete compromise of all network devices managed by Cisco DNA Center, allowing lateral movement, data exfiltration, and network disruption.
Likely Case
Privilege escalation leading to unauthorized configuration changes, network monitoring, or credential harvesting from managed devices.
If Mitigated
Limited impact if strong authentication controls, network segmentation, and least privilege access are implemented.
🎯 Exploit Status
Exploitation requires authenticated access but is straightforward once credentials are obtained.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 2.1.2.0 and later
Vendor Advisory: https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-dnac-cmdinj-erumsWh9
Restart Required: Yes
Instructions:
1. Backup Cisco DNA Center configuration. 2. Download and install Cisco DNA Center version 2.1.2.0 or later from Cisco Software Center. 3. Follow Cisco's upgrade documentation for proper installation procedure. 4. Verify successful upgrade and functionality.
🔧 Temporary Workarounds
Restrict Command Runner Access
allLimit access to Command Runner tool and API to only authorized administrators using role-based access controls.
Network Segmentation
allIsolate Cisco DNA Center management network from production networks to limit potential lateral movement.
🧯 If You Can't Patch
- Implement strict access controls and multi-factor authentication for all Cisco DNA Center administrative accounts.
- Monitor and audit all Command Runner tool usage and API calls for suspicious activity.
🔍 How to Verify
Check if Vulnerable:
Check Cisco DNA Center version via GUI (System > About) or CLI. Versions below 2.1.2.0 are vulnerable.Check Version:
show versionVerify Fix Applied:
Confirm version is 2.1.2.0 or later and test Command Runner functionality with safe commands.📡 Detection & Monitoring
Log Indicators:
- Unusual Command Runner API calls
- Suspicious CLI command execution patterns
- Multiple failed authentication attempts followed by Command Runner access
Network Indicators:
- Unusual outbound connections from Cisco DNA Center to managed devices
- Anomalous command traffic patterns
SIEM Query:
source="cisco_dna_center" AND (event_type="command_runner" OR api_endpoint="/api/command-runner") AND command="*;*" OR command="*|*" OR command="*&*"