CVE-2026-21643: Fortinet FortiClient EMS SQL Injection Vulnerability

CISA Known Exploited Vulnerability (KEV)

Description

Fortinet FortiClient EMS contains a SQL injection vulnerability that may allow an unauthenticated attacker to execute unauthorized code or commands via specifically crafted HTTP requests.

Required action (CISA)

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Notes

https://fortiguard.fortinet.com/psirt/FG-IR-25-1142 ; https://nvd.nist.gov/vuln/detail/CVE-2026-21643

Weakness behind it

CISA records this vulnerability as an instance of CWE-89. From there the chain continues into CAPEC attack patterns and ATT&CK techniques, all inside this corpus.

References

• NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-21643
• KEV catalog: https://www.cisa.gov/known-exploited-vulnerabilities-catalog