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.
do firstApply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Can a WAF block it? Partly. The vulnerability is triggered by a specially crafted HTTP request that uploads a file via the upload.cgi endpoint. Since file uploads are normal but the malicious file is crafted to be executable code, a WAF could partly detect unusual file types or contents but might not fully distinguish malicious uploads from legitimate ones. A custom WAF rule can filter HTTP POST requests to upload.cgi with file upload content, but attackers can vary the request. No tracked WAF vendor has published a rule for this CVE yet.
What a custom rule would match: HTTP POST requests to upload.cgi with file upload content
Also consider: patch · custom WAF rule · MIME sniff · sandbox storage
Based on an AI reading of the CVE description, and no vendor rule found yet. We check Cloudflare, AWS, Google Cloud Armor and Azure; for Akamai, Imperva, Fastly, F5, ask your vendor.
Is CVE-2018-4063 being exploited?
Yes. CVE-2018-4063 appears in CISA's Known Exploited Vulnerabilities catalog, which means exploitation in the wild has been confirmed and reported. Treat it as active rather than theoretical, and patch it ahead of higher-scoring vulnerabilities that carry no exploitation evidence.
How severe is CVE-2018-4063?
CVE-2018-4063 is rated High with a CVSS score of 8.8. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2018-4063?
Yes. A fix has been recorded for CVE-2018-4063. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2018-4063 affect?
CVE-2018-4063 affects sierrawireless:aleos. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
- affectedSierra Wireless AirLink ES450 FW 4.9.3
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.
cisa ssvc
- exploitation
- active
- automatable
- no
- technical impact
- total
Assessed by CISA 13 Dec 2025 (SSVC 2.0.3).
timeline
- 6 May 2019Published
- 12 Dec 2025Added to CISA KEV (exploited in the wild) · 2,411 days (about 7 years) later
- 13 Dec 2025CISA SSVC assessment: exploitation active · 1 day later
- 2 Jan 2026CISA remediation due date (US federal agencies) · 20 days later
- 22 May 2026CVE record last updated · 141 days (about 5 months) later
- 2 Nov 2026Analysed by vulneraibility.com · 164 days (about 5 months) later
- Advisoryforescout.com /blog/ot-network-security-threats-industrial-routers-under-attack/
- Linkpacketstormsecurity.com /files/152648/Sierra-Wireless-AirLink-ES450-ACEManager-upload.cgi-Remote-Code-Ex
- Linkics-cert.us-cert.gov /advisories/ICSA-19-122-03
- Linksecurityfocus.com /bid/108147
- Linktalosintelligence.com /vulnerability_reports/TALOS-2018-0748
- Linkcisa.gov /known-exploited-vulnerabilities-catalog?field_cve=CVE-2018-4063
sources
- CVE List (CVE.org): description, affected versions, references; CVE Terms of Use
- NVD: CVSS and CPE data
- CISA KEV catalog: exploitation, date added, due date
- CISA Vulnrichment (ADP): SSVC decision points
- FIRST EPSS: exploit probability and percentile
- Summary, impact and triage tags: written by our AI analysis pipeline from the sources above. Check them against the sources.