CVE-2023-20223
📋 TL;DR
This vulnerability in Cisco DNA Center allows unauthenticated remote attackers to read and modify data in an internal service repository due to insufficient API access controls. It affects Cisco DNA Center devices with vulnerable versions, potentially compromising sensitive network management data.
💻 Affected Systems
- Cisco DNA Center
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
An attacker could gain unauthorized access to critical internal service data, leading to data theft, manipulation, or disruption of network management functions.
Likely Case
Attackers may exploit this to read or modify configuration data, potentially causing network instability or unauthorized changes.
If Mitigated
With proper patching and network segmentation, the risk is reduced to minimal, limiting exposure to trusted networks only.
🎯 Exploit Status
Exploitation involves sending crafted API requests, which is straightforward given the unauthenticated nature.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 2.3.7.6 or later
Vendor Advisory: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-dnac-ins-acc-con-nHAVDRBZ
Restart Required: Yes
Instructions:
1. Log into Cisco DNA Center. 2. Navigate to System > Software Updates. 3. Download and install version 2.3.7.6 or later. 4. Restart the device as prompted.
🔧 Temporary Workarounds
Network Segmentation
allRestrict access to Cisco DNA Center API endpoints to trusted internal networks only.
Use firewall rules to block external access to Cisco DNA Center ports (e.g., TCP 443).
🧯 If You Can't Patch
- Implement strict network access controls to limit exposure to the Cisco DNA Center device.
- Monitor API logs for unusual or unauthorized access attempts.
🔍 How to Verify
Check if Vulnerable:
Check the Cisco DNA Center version via the web interface or CLI; if it is below 2.3.7.6, it is vulnerable.Check Version:
ssh admin@<dnac-ip> show version | grep 'Cisco DNA Center'Verify Fix Applied:
After patching, confirm the version is 2.3.7.6 or higher and test API access controls.📡 Detection & Monitoring
Log Indicators:
- Unusual API requests from unauthenticated sources, spikes in access to internal service endpoints.
Network Indicators:
- Traffic to Cisco DNA Center API endpoints from unexpected IP addresses.
SIEM Query:
source="Cisco DNA Center" AND (event_type="api_access" AND user="unauthenticated")