Hazard

Is CVE-2026-21643 being exploited?

Weaponised and widely attempted

Reliable public exploit code exists, or mass exploitation attempts are probable. Patch inside days, not weeks.

Fortinet FortiClient EMS SQL Injection Vulnerability

Fortinet · FortiClient EMS

CVSS 9.8 EPSS 94% no public exploit indexed Fix deadline passed 16 April 2026

What it is

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.

Why we say that

  • EPSS puts exploitation in the next 30 days at 94%
  • CISA's federal remediation deadline (2026-04-16) has passed
  • CVSS 9.8 critical
  • Listed in the CISA Known Exploited Vulnerabilities catalogue

Every line above comes from a named public source. Where the evidence is thin, we say so rather than inventing confidence — see methodology.

What to do

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 it costs when this goes wrong

This is where UK enforcement meets the vulnerability record. Where an unfixed vulnerability leads to a breach, the ICO treats it as a security failure under UK GDPR. Recent cases:

All UK cases caused by unpatched software →