CVE-2019-11857
📋 TL;DR
CVE-2019-11857 is an input validation vulnerability in AceManager of Sierra Wireless ALEOS that allows attackers to access sensitive system information without proper authentication. This affects Sierra Wireless routers and gateways running vulnerable ALEOS versions. The vulnerability stems from insufficient sanitization of user inputs in the management interface.
💻 Affected Systems
- Sierra Wireless routers and gateways with ALEOS
📦 What is this software?
Aleos by Sierrawireless
Aleos by Sierrawireless
Aleos by Sierrawireless
⚠️ Risk & Real-World Impact
Worst Case
Attackers could obtain sensitive system information including credentials, configuration details, and network topology, potentially leading to full system compromise and lateral movement within the network.
Likely Case
Unauthorized access to sensitive system information that could be used for reconnaissance and planning further attacks against the device or connected systems.
If Mitigated
With proper network segmentation and access controls, the impact is limited to information disclosure within the isolated management network segment.
🎯 Exploit Status
The vulnerability allows information disclosure without authentication, making it relatively easy to exploit if the management interface is accessible.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: ALEOS 4.12.0, 4.9.5, or 4.4.9 and later
Vendor Advisory: https://source.sierrawireless.com/resources/security-bulletins/sierra-wireless-technical-bulletin---swi-psa-2020-004/
Restart Required: Yes
Instructions:
1. Download the appropriate firmware update from Sierra Wireless support portal. 2. Backup current configuration. 3. Apply firmware update through web interface or CLI. 4. Reboot device. 5. Verify firmware version and functionality.
🔧 Temporary Workarounds
Disable AceManager Interface
allDisable the vulnerable AceManager interface if not required for operations
configure terminal
no ace-manager enable
write memory
Restrict Network Access
allImplement network access controls to limit access to the management interface
configure terminal
access-list 100 deny ip any any
interface management
ip access-group 100 in
write memory
🧯 If You Can't Patch
- Implement strict network segmentation to isolate management interfaces from untrusted networks
- Deploy network-based intrusion detection systems to monitor for exploitation attempts
🔍 How to Verify
Check if Vulnerable:
Check ALEOS version via web interface or CLI command 'show version' and compare against vulnerable versionsCheck Version:
show versionVerify Fix Applied:
Verify ALEOS version is 4.12.0, 4.9.5, 4.4.9 or later using 'show version' command📡 Detection & Monitoring
Log Indicators:
- Unusual access patterns to AceManager interface
- Multiple failed authentication attempts followed by information disclosure requests
Network Indicators:
- Unusual traffic to management interface ports (typically 80/443)
- Requests to sensitive information endpoints without proper authentication
SIEM Query:
source="aleos_logs" AND (event_type="access_denied" OR event_type="information_disclosure") AND dest_port IN (80, 443)