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

Is it exploited?

Yes. CISA added it to the Known Exploited Vulnerabilities catalog on 13 Apr 2026, 66 days after the CVE record was published.

How likely is exploitation in the next 30 days?

97.7%

EPSS score, percentile 99.9 of all scored records

How severe?

9.1 Critical

CVSS v3.1 base score, given by the CNA

What should I do?

Required action (CISA), due 16 Apr 2026: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

The CVE record links no vendor advisory, patch or mitigation.

Which versions are affected?

Affected: 7.4.4

Versions by product

Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

What to do

CISA due date for this action: 16 April 2026.

Solution (from the CVE record)

Upgrade to upcoming FortiClientEMS version 8.0.0 or above Upgrade to FortiClientEMS version 7.4.5 or above

Advisories and patches

The CVE record links no vendor advisory, patch or mitigation.

Linked from CISA's catalog entry

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

Affected products and versions

As listed in the CVE record.

Versions not listed are: unaffected.

Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

About this vulnerability

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.

Summary: CISA's KEV catalog, as of 28 Oct 2026.

• CISA added CVE-2026-21643 to its Known Exploited Vulnerabilities (KEV) catalog on 13 Apr 2026.
• CISA's ransomware flag for this entry is "Unknown": no evidence of ransomware use in the catalog, which is not proof of none.
• The due date CISA sets for the required action is 16 Apr 2026.
• The CVE record was published on 6 Feb 2026, 66 days before it was added to KEV.
• The CVE record carries a CVSS v3.1 base score of 9.1 (Critical), given by its CNA.
• FIRST's EPSS model puts the probability of exploitation in the next 30 days at 97.7% (percentile 99.9), as of 28 Oct 2026.
• CISA's SSVC assessment in the CVE record: exploitation active, automatable yes, technical impact total.

Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026. About the data.

Description

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.

Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

Weakness

• CWE-89

CWE and CAPEC are maintained by MITRE; the entries are those named in the CVE record and the KEV entry.

Timeline

References

• https://fortiguard.fortinet.com/psirt/FG-IR-25-1142

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