What it is
CVE-2018-9866 is an unauthenticated vulnerability affecting SonicWall Global Management System (GMS). A vulnerability in lack of validation of user-supplied parameters pass to XML-RPC calls on SonicWall Global...
Vulnerability report
Global Management System (GMS)
SonicWall / Global Management System (GMS) · 8.1 and earlier
Decision summary
Direct answers before the deeper technical record.
What it is
CVE-2018-9866 is an unauthenticated vulnerability affecting SonicWall Global Management System (GMS). A vulnerability in lack of validation of user-supplied parameters pass to XML-RPC calls on SonicWall Global...
Is it exploited?
Yes. Previdian tracks this CVE as a known exploited vulnerability. Confidence is high. Also confirmed by third-party sources.
Who is affected?
SonicWall / Global Management System (GMS) 8.1 and earlier.
What should we do?
Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.
Overview
A vulnerability in lack of validation of user-supplied parameters pass to XML-RPC calls on SonicWall Global Management System (GMS) virtual appliance's, allow remote user to execute arbitrary code.
This vulnerability affected GMS version 8.1 and earlier.
Exploitation evidence
Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.
The Shadowserver
A trusted third party reported exploitation.
Per-source evidence links for KEV attestations are available through the Previdian Pro API.
Learn about Pro API access| Source | Added |
|---|---|
| The Shadowserver First | 2025-04-26 00:00 UTC |
Detection
Make the evidence actionable in scanner, SOC, and edge-control workflows.
Request targets and User-Agents available in Pro. Callback host details available in Enterprise.
No scanner integrations recorded yet.
No Previdian virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.
Learn about virtual patches →No detection artifacts or sensor request patterns are available for this CVE yet.
Check back as sensor telemetry and scanner integrations are updated.
Risk and context
CVSS v3.1
Potential damage if exploited. Separate from whether attackers are using it.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
4.5%
Estimated chance of exploitation in the next 30 days. Previdian's warning comes from evidence, not this score.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
AV:N/AC:L/Au:N/C:P/I:P/A:P
Timeline
00:00 UTC
High-confidence, third-party attested exploitation
20:00 UTC
Vulnerability disclosed publicly
00:00 UTC
Identifier reserved by the CNA
Pro API
Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.
GET /api/v2/pro/kevs/CVE-2018-9866
Free JSON includes basic KEV fields{
"cve_id": "CVE-2018-9866",
"confidence": "High",
"cvss_score": 9.8,
"cvss_estimated": false,
"epss_score": 0.04504,
"exploit_status": {
"exploited_in_the_wild": true,
"active_exploitation_observed": false
},
"sensor_telemetry": { "attempts": 0, "sensors": 0 }
}