CVE-2025-46731 is a high-severity remote code execution (RCE) vulnerability affecting Craft CMS versions 4.x prior to 4.14.13 and 5.x prior to 5.6.15. Craft CMS is a popular content management system used for building websites and web applications. The vulnerability arises from improper neutralization of special elements in the Twig template engine, classified under CWE-1336. Specifically, this is a Server-Side Template Injection (SSTI) vulnerability that allows an attacker with administrator privileges and with the ALLOW_ADMIN_CHANGES setting enabled to execute arbitrary code on the server. The vulnerability requires no user interaction and no additional authentication beyond administrator access, making it a significant risk in environments where admin accounts are compromised or misused. Exploitation could lead to full system compromise, data theft, or service disruption. The CVSS 4.0 base score is 7.3, reflecting high impact on confidentiality, integrity, and availability, with low attack complexity but requiring high privileges. No known exploits are currently reported in the wild, but the potential impact warrants urgent patching. The vendor has released fixed versions 4.14.13 and 5.6.15 to address the issue. Organizations running affected versions should prioritize upgrading to these patched releases to mitigate the risk.

For European organizations, the impact of this vulnerability can be substantial, especially for those relying on Craft CMS for critical web infrastructure, e-commerce platforms, or internal portals. Successful exploitation could lead to unauthorized code execution, enabling attackers to steal sensitive data, manipulate website content, deploy malware, or disrupt services. This could result in reputational damage, regulatory non-compliance (e.g., GDPR violations due to data breaches), financial losses, and operational downtime. Since the vulnerability requires administrator access, the risk is heightened in environments with weak access controls or compromised admin credentials. Additionally, the ability to execute arbitrary code on web servers can be leveraged to pivot into internal networks, increasing the attack surface. Given the widespread use of CMS platforms in Europe, especially among SMEs and public sector entities, the threat could affect a broad range of sectors including government, finance, healthcare, and retail.

1. Immediate upgrade to Craft CMS versions 4.14.13 or 5.6.15, which contain patches for this vulnerability. 2. Restrict and monitor administrator access rigorously; implement strong multi-factor authentication (MFA) for all admin accounts to reduce the risk of credential compromise. 3. Disable the ALLOW_ADMIN_CHANGES setting if not required, as its enablement is a prerequisite for exploitation. 4. Conduct regular audits of admin account activity and review logs for suspicious behavior indicative of attempted exploitation. 5. Employ web application firewalls (WAFs) with custom rules to detect and block SSTI attack patterns targeting Twig templates. 6. Segment and harden web server environments to limit lateral movement in case of compromise. 7. Educate administrators on secure configuration and the risks of elevated privileges. 8. Maintain up-to-date backups and incident response plans to enable rapid recovery if exploitation occurs.