CVE-2026-35616 — Forticlientems
CRITICALCVE-2026-35616 is a critical-severity (CVSS 9.8) CWE-284 vulnerability in fortinet forticlientems. It is in CISA's Known Exploited Vulnerabilities catalog (added 2026-04-06) — treat it as actively exploited and patch now. No vendor fix is recorded yet; mitigation options are listed below.
A improper access control vulnerability in Fortinet FortiClientEMS 7.4.5 through 7.4.6 may allow an unauthenticated attacker to execute unauthorized code or commands via crafted requests.
Exploitation Status
Actively exploited in the wild
- Confirmed by CISA's Known Exploited Vulnerabilities catalog on 2026-04-06. Federal agencies were required to remediate by 2026-04-09.
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- A successful exploit gives an attacker total control of the affected component, not partial access.
Exploitation and automatability from CISA (KEV catalog and SSVC triage) for CVE-2026-35616.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2026-35616 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 395,249 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Description
A improper access control vulnerability in Fortinet FortiClientEMS 7.4.5 through 7.4.6 may allow an unauthenticated attacker to execute unauthorized code or commands via crafted requests.
Affected Products
forticlientemsfortinetResearch use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Vendor / applianceDetect
Inventory every fortinet forticlientems deployment and check each version against the affected-products list above.
Remediation status
No patch has shipped for CVE-2026-35616 yet — track the fortinet forticlientems advisory for a fixed release and apply the workarounds below in the meantime.
Mitigate without a patch
Put an independent control in front of the weakness: restrict the affected endpoint or interface to trusted networks, require an additional authentication factor or proxy-level check, and invalidate existing sessions and credentials in case the flaw has already been used. Alongside that, restrict the management interface to trusted networks and apply the vendor's recommended configuration mitigations.
How to detect CVE-2026-35616
A community-maintained Nuclei template exists for this CVE. You can scan for it directly:
nuclei -id cve-2026-35616 -u https://target- Template
- FortiClient EMS - Authentication Bypass
- Severity
- high
- Impact
- If spoofing X-SSL-CLIENT-VERIFY changes backend behavior, Apache is likely not stripping the header before Django, indicating the target is still vulnerable.
- Remediation
- Apply Fortinet hotfix FG-IR-26-099 or upgrade to FortiClient EMS 7.4.7+.
Template by ProjectDiscovery nuclei-templates (ritikchaddha), MIT licensed. View the full template. Scan only systems you are authorised to test.
Frequently Asked Questions
Is CVE-2026-35616 being exploited in your environment?
Detect and block the exploit chain at execution, on systems you cannot patch yet.