CVE-2019-1646
📋 TL;DR
This vulnerability in Cisco SD-WAN Solution allows authenticated local attackers to escalate privileges by sending crafted CLI commands due to improper input sanitization. Attackers can modify device configurations and access sensitive data. Only users with local CLI access to affected Cisco SD-WAN devices are impacted.
💻 Affected Systems
- Cisco SD-WAN Solution
📦 What is this software?
Sd Wan by Cisco
⚠️ Risk & Real-World Impact
Worst Case
Attacker gains full administrative control over the SD-WAN device, modifies routing configurations, intercepts network traffic, and uses the device as a pivot point to attack other network segments.
Likely Case
Privileged attacker modifies local device configurations to maintain persistence, exfiltrates sensitive configuration data, or disrupts SD-WAN operations.
If Mitigated
Attack is prevented through proper access controls, command filtering, and network segmentation limiting local access to authorized administrators only.
🎯 Exploit Status
Requires authenticated local access but exploitation is straightforward once access is obtained.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Refer to Cisco Security Advisory for specific fixed versions
Vendor Advisory: https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190123-sdwan-escal
Restart Required: Yes
Instructions:
1. Review Cisco Security Advisory for affected versions. 2. Download and install the fixed software version from Cisco. 3. Reboot the device after installation. 4. Verify the patch is applied correctly.
🔧 Temporary Workarounds
Restrict Local CLI Access
allLimit local CLI access to only authorized administrators using AAA controls and role-based access.
configure terminal
aaa authentication login default local
aaa authorization exec default local
username admin privilege 15 secret yourpassword
Implement Command Filtering
allUse command authorization to restrict which CLI commands users can execute.
configure terminal
privilege exec level 1 show
privilege exec level 15 configure terminal
🧯 If You Can't Patch
- Implement strict access controls to limit local CLI access to trusted administrators only
- Monitor CLI command logs for suspicious privilege escalation attempts
🔍 How to Verify
Check if Vulnerable:
Check current software version against affected versions listed in Cisco Security AdvisoryCheck Version:
show versionVerify Fix Applied:
Verify installed version matches or exceeds the fixed version specified in Cisco advisory📡 Detection & Monitoring
Log Indicators:
- Unusual privilege escalation in CLI logs
- Configuration changes from non-admin users
- Failed authentication attempts followed by successful privilege changes
Network Indicators:
- Unexpected configuration changes to routing or security policies
- Unauthorized administrative sessions
SIEM Query:
source="cisco_sdwan" AND (event_type="privilege_escalation" OR command="configure terminal" AND user!="admin")