What is CVE-2018-4063?

CVE-2018-4063 is a high-severity vulnerability in Sierrawireless Airlink Es440, classified under Unrestricted Upload of File with Dangerous Type. CVSS score: 8.8/10. Published 2019-05-06.

How severe is CVE-2018-4063?

High severity. CVSS v3 base score is 8.8 out of 10.

Is CVE-2018-4063 known to be exploited?

Yes. CVE-2018-4063 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2025-12-12), indicating it is being actively exploited.

Arbitrary file upload in Sierrawireless Airlink Es440

CVE-2018-4063

An exploitable remote code execution vulnerability exists in the upload.cgi functionality of Sierra Wireless AirLink ES450 FW 4.9.3. A specially crafted HTTP request can upload a file, resulting in executable code being uploaded, and routable, to the webserver. An attacker can make an authenticated HTTP request to trigger this vulnerability.

Vulnerability class: Unrestricted File Upload

Published 2019-05-06 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.271 (98.0th percentile), scored 2026-10-18.

Moderate probability of exploitation in the next 30 days — watch for active exploitation reports. 98th percentile — 98.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.271 · newest: 0.271 · change: 0.000

Affected products

Weakness classification (CWE)

CWE-434 — Unrestricted Upload of File with Dangerous Type

CISA KEV (Known Exploited Vulnerabilities)

This CVE is on the CISA KEV catalog, added on 2025-12-12. CISA KEV inclusion means CISA has confirmed in-the-wild exploitation; US federal agencies are required to remediate within a published due date.

BOD 22-01 due date: 2026-01-02.

Required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

References

packetstormsecurity.com/files/152648/Sierra-Wireless-AirLink-ES450-ACEManager-u… (Exploit, VDB Entry)
ics-cert.us-cert.gov/advisories/ICSA-19-122-03 (US Government Resource, Third Party Advisory)
www.securityfocus.com/bid/108147 (vdb-entry, Broken Link)
talosintelligence.com/vulnerability_reports/TALOS-2018-0748 (Exploit, Third Party Advisory)
134c704f-9b21-4f2e-91b3-4a467353bcc0 (US Government Resource)
134c704f-9b21-4f2e-91b3-4a467353bcc0 (Exploit, Third Party Advisory)

Frequently asked questions

What is CVE-2018-4063?: CVE-2018-4063 is a high-severity vulnerability in Sierrawireless Airlink Es440, classified under Unrestricted Upload of File with Dangerous Type. CVSS score: 8.8/10. Published 2019-05-06.
How severe is CVE-2018-4063?: High severity. CVSS v3 base score is 8.8 out of 10.
Is CVE-2018-4063 known to be exploited?: Yes. CVE-2018-4063 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2025-12-12), indicating it is being actively exploited.