An improper neutralization of special elements used in SQL commands in Fortinet FortiClientEMS 7.4.4 may allow an unauthenticated attacker to execute unauthorized code or commands through specially crafted HTTP requests. This vulnerability, tracked as CVE‑2026‑21643 with a CVSS score of 9.1, poses a critical risk. Read this Cybersecurity Threat Advisory to understand the threat and how to protect your environment.
What is the threat?
This vulnerability allows an attacker to inject malicious SQL commands into database queries through the FortiClientEMS web GUI—without needing valid credentials. Because the attack can be performed remotely and without authentication, successful exploitation enables the attacker to execute arbitrary code or system commands on the FortiClientEMS server.
This foothold could allow adversaries to:
- Move laterally to other systems
- Deploy malware or ransomware
- Manipulate endpoint policies managed by FortiClientEMS
The combination of remote access, no login requirement, and code execution on a central management system makes this a critical, high‑priority threat.
Why is it noteworthy?
The issue is significant because it pairs high impact with low attacker effort. FortiClientEMS is a high‑value target due to its ability to manage many endpoints. A successful exploit could:
- Compromise a high‑privilege, centrally trusted management server
- Enable lateral movement and deeper network compromise
- Allow widescale malware or ransomware deployment
- Be easily automated and mass exploited due to the SQL injection mechanism
What is the exposure or risk?
Any attacker who can reach the FortiClientEMS web interface can exploit this flaw to run code or commands on the server. This effectively hands them control of a critical security platform, giving them the opportunity to:
- Push malicious configurations or software to endpoints
- Disable protective controls
- Steal credentials or sensitive data
- Spread malware or ransomware across the network
Because the compromise begins with a central management system, the operational and business impact can be severe. Patching and restricting access should be treated as an immediate priority.
What are the recommendations?
Barracuda recommends taking the following actions to secure your environment:
- Identify any FortiClientEMS (or other affected Fortinet products) in your environment and update them to Fortinet’s latest fixed version.
- Ensure patches are deployed across production, staging, and DR environments.
- Remove direct internet exposure of the FortiClientEMS GUI.
- Restrict access to trusted administrative networks only (e.g., VPN, jump hosts).
- Implement strict firewall rules so only required management IP ranges can access the interface.
- Deploy a WAF or IPS in front of the FortiClientEMS web interface to detect and block SQL injection attempts.
- Apply or update security signatures/rules that target SQL injection and Fortinet‑related exploits.
- Review FortiClientEMS logs for unusual access patterns, unexpected IPs, or anomalous API/GUI activity.
- Check for suspicious admin accounts, configuration changes, scheduled tasks, or unknown processes on the server.
- If compromise is suspected, follow full incident response procedures (isolate, investigate, eradicate, recover).
References
For more in-depth information about the recommendations, please visit the following links:
- https://thehackernews.com/2026/02/fortinet-patches-critical-sqli-flaw.html?m=1
- https://socprime.com/blog/cve-2026-21643-vulnerability/
- https://community.opentextcybersecurity.com/vulnerability-vault-228/critical-fortinet-forticlientems-flaw-allows-remote-code-execution-363418
If you have any questions about this Cybersecurity Threat Advisory, don’t hesitate to get in touch with Barracuda Managed XDR’s Security Operations Center.
This post originally appeared on Smarter MSP.