Exploited CVEs / Fortinet / CVE-2026-21643
CVE-2026-21643
Fortinet FortiClient EMS SQL Injection Vulnerability. Exploitation in the wild is confirmed by CISA, not predicted. Federal agencies were required to remediate by 2026-04-16 (that deadline has passed); treat that date as the outer bound for your own environment. The fix is in the vendor advisory: Fortinet PSIRT Advisories, linked below.
Actively exploited Fortinet FortiClient EMS vulnerability, Critical severity, CVSS 9.8. Added to the CISA KEV catalog 2026-04-13.
Risk summary
Updated July 26, 2026. Data refreshed on every build from MSRC, CISA KEV, and FIRST EPSS.
Senserva AI Opinion for CVE-2026-21643
A SQL injection in Fortinet FortiClient EMS lets an unauthenticated attacker execute code or commands through crafted HTTP requests, rated Critical at CVSS 9.8 with a 94% EPSS score. CISA confirmed exploitation on 2026-04-13. EMS manages the FortiClient agents on your endpoints, so a compromised server can be leveraged against the entire managed fleet.
Do this: Patch FortiClient EMS immediately and verify the management interface is not exposed to the internet.
AI-generated from public data, 2026-07-07. Verify against the vendor advisory before acting.
Senserva AI Opinion and rich prompt for CVE-2026-21643
Copy this prompt into Claude, ChatGPT, or Copilot. The facts are included, sourced from this page.
Full tracking and change history for CVE-2026-21643
Published and last-revised dates are authoritative, from Microsoft MSRC (or the CISA KEV date-added). Senserva additionally records day-to-day changes from 2026-07-07, refreshed several times a day; the change count reflects that forward-only tracking.
CISA required action
Federal (BOD 22-01) remediation due date: 2026-04-16 (past due).
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Official fix for CVE-2026-21643
The authoritative fix and affected-version list are published by the vendor. Find the FortiClient EMS advisory on Fortinet PSIRT Advisories.
Common questions about CVE-2026-21643
Is CVE-2026-21643 actively exploited?
Yes. CVE-2026-21643 was added to the CISA Known Exploited Vulnerabilities (KEV) catalog on 2026-04-13, which means exploitation in the wild has been confirmed, not predicted. Its EPSS 30-day exploitation probability is 94%.
What is the CISA deadline and required action for CVE-2026-21643?
CISA set the federal (BOD 22-01) remediation due date at 2026-04-16, which has passed; treat any unremediated system as overdue. The verbatim 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.
What fixes CVE-2026-21643?
The authoritative fix is in the vendor advisory: see Fortinet PSIRT Advisories for the patched FortiClient EMS versions and any workarounds. KEV listing makes this a fix-first item: patch it ahead of higher-CVSS issues nobody is exploiting.
Can I ask my own AI about CVE-2026-21643?
Yes. This page includes a free, ready-to-paste AI prompt containing CVE-2026-21643's key facts: severity, CVSS, EPSS, the KEV date, the CISA due date, and the required action. Copy it into Claude, ChatGPT, or Copilot; the data is refreshed twice a day (5 AM and 3 PM US Central).
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Authoritative references
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