CVE-2021-1484
📋 TL;DR
This vulnerability in Cisco SD-WAN vManage Software allows authenticated remote attackers to inject arbitrary commands through the web UI's device template configuration, potentially causing a denial of service (DoS) condition. It affects organizations using Cisco SD-WAN vManage for network management. The vulnerability stems from improper input validation of user-supplied input.
💻 Affected Systems
- Cisco SD-WAN vManage Software
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise allowing command execution with authenticated user privileges, potentially leading to persistent DoS or further network infiltration.
Likely Case
Authenticated attacker causes DoS condition on the vManage system, disrupting SD-WAN management operations.
If Mitigated
Limited impact with proper network segmentation and access controls preventing unauthorized access to the vManage interface.
🎯 Exploit Status
Exploitation requires authenticated access to the vManage web UI. The vulnerability is in the device template configuration feature.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 20.6.1 and later
Vendor Advisory: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-vman-cmdinj-nRHKgfHX
Restart Required: Yes
Instructions:
1. Download the updated software from Cisco's support portal. 2. Backup current configuration. 3. Install the update following Cisco's SD-WAN upgrade procedures. 4. Verify the system is running version 20.6.1 or later.
🔧 Temporary Workarounds
No official workarounds
allCisco states there are no workarounds that address this vulnerability
🧯 If You Can't Patch
- Restrict access to vManage web UI to only authorized administrators using network segmentation and firewall rules
- Implement strict authentication controls and monitor for suspicious activity in vManage logs
🔍 How to Verify
Check if Vulnerable:
Check the vManage software version via the web UI (System > Software) or CLI using 'show version' commandCheck Version:
show version | include VersionVerify Fix Applied:
Verify the system is running version 20.6.1 or later and test device template configuration functionality📡 Detection & Monitoring
Log Indicators:
- Unusual device template configuration changes
- Multiple failed authentication attempts followed by template modifications
- System logs showing unexpected process execution
Network Indicators:
- Unusual traffic patterns to vManage web UI
- Multiple authentication requests from single source
SIEM Query:
source="vmanage" AND (event_type="template_modification" OR event_type="command_execution")