MStore API - Security Vulnerability (CVE-2026-16038)

AI enriched 97 days ago (2026-08-08 23:44 UTC)

Technical Summary

The MStore API WordPress plugin before 4.21.0 does not verify the payment with the payment gateway before marking an order as paid on several of its payment-completion endpoints, allowing an unauthenticated attacker to mark an arbitrary order fully paid without paying and obtain goods or services for free.

Potential Impact

Severity is CRITICAL (CVSS 9.1). Depending on deployment context, affected components may be exposed to unauthorized actions or data integrity risk.

Exploitability Assessment

Exploitability is assessed as High based on low-bar exploit prerequisites.

Primary risk drivers: low-bar exploit prerequisites

Mitigation Recommendations

Validate affected product versions, prioritize patching, and monitor references for vendor remediation guidance. If immediate patching is not possible, apply compensating controls and limit exposure of vulnerable surfaces.

Detection & Monitoring

Track authentication anomalies, unexpected file writes, and suspicious plugin API activity around affected components.

Business Impact Lens

AI risk score 91/100 (Critical, High) with priority P1 Immediate. Prioritize remediation where affected components process customer data, admin sessions, or Internet-exposed workflows.