The Fortinet FortiWeb product, a widely used web application firewall, suffers from an OS command injection vulnerability identified as CVE-2025-58034. This vulnerability arises from improper neutralization of special elements in user-supplied input, allowing an authenticated attacker to execute arbitrary operating system commands on the underlying system. Exploitation requires the attacker to first authenticate to the FortiWeb device, then leverage this flaw via crafted HTTP requests or CLI commands to execute unauthorized code. The vulnerability has a CVSS score of 6.7, indicating medium severity, but it has been actively exploited in the wild, increasing its risk profile. Fortinet has addressed the issue in FortiWeb versions 8.0.2 and above, 7.6.6 and above, 7.4.11 and above, 7.2.12 and above, and 7.0.12 and above, recommending immediate upgrades. The flaw was responsibly disclosed by a Trend Micro researcher. Notably, Fortinet patched another critical FortiWeb vulnerability (CVE-2025-64446) silently in version 8.0.2, raising concerns about transparency. The U.S. Cybersecurity and Infrastructure Security Agency (CISA) has included CVE-2025-58034 in its Known Exploited Vulnerabilities catalog, urging federal agencies to patch promptly. The vulnerability could allow attackers to gain unauthorized control over FortiWeb devices, potentially leading to data breaches, service disruption, or further network compromise. The requirement for authentication limits exploitation to attackers with some level of access, but the ability to execute OS commands elevates the threat significantly.

For European organizations, exploitation of CVE-2025-58034 could lead to unauthorized execution of commands on FortiWeb devices, compromising the confidentiality, integrity, and availability of protected web applications and backend systems. Given FortiWeb's role as a web application firewall, attackers could bypass security controls, manipulate traffic, or deploy further malware within the network. This could result in data breaches, service outages, and loss of trust. Critical infrastructure sectors such as finance, healthcare, government, and telecommunications that rely on FortiWeb for web application security are particularly at risk. The active exploitation in the wild increases the urgency, as attackers may use this vulnerability to establish persistent footholds or pivot within networks. The requirement for authentication means insider threats or compromised credentials could facilitate attacks. Additionally, the lack of early advisory communication from Fortinet may have delayed defensive measures, increasing exposure time. European organizations face regulatory risks under GDPR if breaches occur due to unpatched vulnerabilities. Overall, the impact ranges from moderate disruption to severe compromise depending on the attacker's objectives and network segmentation.

European organizations should immediately verify their FortiWeb versions and upgrade to the patched releases: 8.0.2 or above, 7.6.6 or above, 7.4.11 or above, 7.2.12 or above, or 7.0.12 or above. Prioritize patching in environments exposed to untrusted networks. Strengthen authentication mechanisms to prevent unauthorized access, including enforcing multi-factor authentication (MFA) for FortiWeb administrative access. Conduct thorough audits of user accounts and credentials to detect and remove any unauthorized or stale accounts. Monitor FortiWeb logs for unusual or suspicious command execution attempts. Implement network segmentation to limit FortiWeb management interface exposure. Use intrusion detection and prevention systems to detect exploitation attempts. Establish incident response plans specific to FortiWeb compromise scenarios. Engage with Fortinet support and threat intelligence sources for updates on emerging exploitation techniques. Finally, consider deploying compensating controls such as web application firewalls in front of FortiWeb devices or additional endpoint monitoring to detect lateral movement.