Exploited vulnerabilities / CVE-2026-21643
Confirmed exploited · SQL injection · Fortinet FortiClient EMSCVE-2026-21643
Fortinet FortiClient EMS SQL injection, confirmed exploited in the wild.
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.
| CISA's name for it | Fortinet FortiClient EMS SQL Injection Vulnerability |
|---|---|
| Vendor and product | Fortinet · FortiClient EMS |
| Type | SQL injection · CWE-89 |
| Exploited | Confirmed by CISA listed 13 April 2026 |
| Likelihood | one of the most likely to be exploited of every vulnerability tracked |
| Deadline | 16 April 2026 · already passed |
| Used in ransomware | Not reported |
| Advisories | fortiguard.fortinet.com ↗ · nvd.nist.gov ↗ |
Three steps, in this order
Apply the vendor fix.
Treat the database behind it as exposed: rotate the credentials it stores and check for new admin users.
Put a web application firewall rule in front of the endpoint until patched.
| CISA's 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. |
|---|
Know before someone else finds it
Threat Landscape Monitoring fingerprints the software your internet-facing hosts disclose and matches it, every day, against this list and the exploitation scores. When a new entry touches something you run, you are told once, with the host and the fix. The free plan covers one domain.
CVE-2026-21643 in short
Is CVE-2026-21643 being exploited?
Yes. CISA added CVE-2026-21643 to its Known Exploited Vulnerabilities catalogue on 13 April 2026, which it does only on evidence of exploitation in the wild.
What is the CISA deadline for CVE-2026-21643?
US federal agencies must remediate it by 16 April 2026. Everyone else should treat that date as the latest safe point to patch an internet-facing system.
How likely is CVE-2026-21643 to be exploited in the next 30 days?
FIRST's Exploit Prediction Scoring System gives it 98%, the 99th percentile of every CVE it scores.
How do I fix CVE-2026-21643?
Apply the vendor fix. Treat the database behind it as exposed: rotate the credentials it stores and check for new admin users. Put a web application firewall rule in front of the endpoint until patched.
Other Fortinet vulnerabilities being exploited
| CVE | Product | Type | Listed |
|---|---|---|---|
| CVE-2025-61624 | Multiple Products | path traversal | 16 October 2026 |
| CVE-2026-104286 | FortiMail | path traversal | 1 October 2026 |
| CVE-2025-25249 | Multiple Products | memory corruption | 9 September 2026 |
| CVE-2025-68686 | FortiOS | exploited vulnerability | 27 July 2026 |
| CVE-2026-25089 | FortiSandbox | command injection | 16 July 2026 |
| CVE-2026-39808 | FortiSandbox | command injection | 16 July 2026 |
Sources: CISA Known Exploited Vulnerabilities catalogue (released 10 November 2026) and FIRST EPSS. Page compiled automatically by SAK T.L.M, the threat-intelligence tool of SAK T.E.C, on 13 November 2026.