CVE-2026-21643
Fortinet FortiClient EMS SQL Injection Vulnerability
Fortinet FortiClient EMS
An improper neutralization of special elements used in an sql command ('sql injection') vulnerability in Fortinet FortiClientEMS 7.4.4 may allow an unauthenticated attacker to execute unauthorized code or commands via specifically crafted HTTP requests.
Exploitation status
CISA Known Exploited Vulnerabilities
Listed by CISA on 13 April 2026. US federal agencies were required to remediate it by 16 April 2026.
EPSS — exploitation probability
FIRST puts the probability of exploitation activity in the next 30 days at 97.7%, which is higher than 99.9% of all scored vulnerabilities. EPSS is a forecast of activity, not a measure of severity, and it is rescored daily.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Frequently asked questions
Is CVE-2026-21643 being exploited by ransomware groups?
No ransomware group in this database is currently recorded as exploiting CVE-2026-21643.
What does CVE-2026-21643 affect?
CVE-2026-21643 affects Fortinet FortiClient EMS. An improper neutralization of special elements used in an sql command ('sql injection') vulnerability in Fortinet FortiClientEMS 7.4.4 may allow an unauthenticated attacker to execute unauthorized code or commands via specifically crafted HTTP requests.
How severe is CVE-2026-21643?
CVE-2026-21643 is rated CRITICAL with a CVSS base score of 9.8. EPSS puts the probability of exploitation in the next 30 days at 97.7%, higher than 99.9% of all scored vulnerabilities. It is listed in the CISA Known Exploited Vulnerabilities catalog, with a federal remediation deadline of 16 April 2026.
How should organisations respond to CVE-2026-21643?
Apply the vendor patch for Fortinet FortiClient EMS as the first priority, and treat any internet-facing instance as the most urgent. Because this vulnerability is associated with ransomware activity, also review whether the affected systems were reachable before patching, rather than assuming that patching alone closes the incident.