Historical catalog analysis: CISA added this entry on December 12, 2025. The entry reflects catalog information retrieved on August 31, 2026, not a snapshot archived on the inclusion date. Check current vendor guidance before acting.
What the vulnerability is
CVE-2018-4063 is an unrestricted upload of file with dangerous type vulnerability (CWE-434) affecting Sierra Wireless AirLink ALEOS. The flaw allows a user with valid authentication to send a specially crafted HTTP request to the device’s webserver, resulting in the upload of executable code that is routable.
Exposure and applicability
This vulnerability applies to industrial environments utilizing AirLink ALEOS devices for remote connectivity, cellular backhaul, or gateway operations. Because these devices often sit at the perimeter of OT networks to provide remote access for vendors or technicians, an authenticated compromise of the gateway could provide a foothold into the wider control system environment.
It is important to note that some impacted products may be end-of-life (EoL) or end-of-service (EoS), meaning official security updates may no longer be available for certain hardware versions.
Remediation priorities
Our analysis suggests the following prioritized actions for OT asset owners:
- Inventory and Lifecycle Audit: Identify all AirLink ALEOS devices in production. Determine if specific units are EoL or EoS, as this dictates whether a patch is possible or if hardware replacement is required.
- Authentication Review: Since exploitation requires authentication, audit all local and remote administrative accounts. Remove unnecessary accounts and ensure strong password policies are enforced to reduce the likelihood of unauthorized authenticated access.
- Network Isolation: For devices that cannot be patched due to EoL status, restrict HTTP/HTTPS management access to a dedicated, isolated management VLAN or via a secure VPN, preventing direct exposure to broader corporate or public networks.
- Decommissioning: In alignment with vendor and CISA suggestions, prioritize the discontinuation of use for devices where mitigations are unavailable or insufficient for the risk profile of the process being controlled.
How to validate remediation
Validation should be performed according to OEM guidance and internal change control processes:
* Version Verification: Confirm that firmware versions match the vendor’s recommended secure releases.
* Access Control Testing: Verify that the web management interface is unreachable from unauthorized network segments.
* Account Audit: Review the device user list to ensure only authorized personnel possess the credentials required to trigger the authenticated request.
Limits and open questions
While CISA has added this vulnerability to the Known Exploited Vulnerabilities (KEV) catalog, it remains unknown if specific ransomware campaigns are utilizing this flaw. Additionally, because some hardware is EoL, there may be no official patch for certain deployments, leaving asset owners with a choice between manual mitigation or full equipment replacement.
Source and editorial note
CVE-2018-4063: Sierra Wireless AirLink ALEOS Unrestricted Upload of File with Dangerous Type Vulnerability · Source date: December 12, 2025 · Retrieved August 31, 2026.
Material facts are tied to the cited primary source. Recommendations are independent defensive analysis unless attributed to the source. Confirm consequential decisions against current authoritative guidance.
Archive date: December 15, 2025. The displayed post date is assigned three days after the source date to organize this retrospective archive; it does not mean this site published the analysis then. First published by this site: September 11, 2026 at 01:38 UTC.
Request an OT security assessment
Protect the systems your operations depend on.
Discuss your industrial environment, prioritize exposure, and establish evidence that safeguards work.
Request an OT assessment ↗