CVE-2022-43686 is a vulnerability affecting Concrete CMS (formerly known as concrete5) versions below 8.5.10 and between 9.0.0 and 9.1.2. The issue arises from the way the system manages the authTypeConcreteCookieMap table, which can be filled up by an attacker, leading to a denial of service (DoS) condition characterized by high system load. Specifically, this vulnerability is classified under CWE-770, which relates to the allocation of resources without limits or throttling, allowing an attacker to exhaust system resources. The vulnerability does not impact confidentiality or integrity but severely affects availability by causing excessive load and potential service disruption. The CVSS 3.1 base score is 6.5 (medium severity), with the vector indicating network attack vector (AV:N), low attack complexity (AC:L), requiring privileges (PR:L), no user interaction (UI:N), unchanged scope (S:U), no confidentiality or integrity impact (C:N/I:N), and high impact on availability (A:H). Exploitation requires some level of privileges, but no user interaction is needed. There are no known exploits in the wild, and no official patches are linked in the provided data. The vulnerability is primarily a resource exhaustion issue that could be triggered remotely by authenticated users, potentially leading to service degradation or outage of Concrete CMS-powered websites.

For European organizations using Concrete CMS within the affected version ranges, this vulnerability poses a significant risk to service availability. Concrete CMS is a popular open-source content management system used by various public sector entities, educational institutions, and private companies across Europe. A successful exploitation could lead to denial of service, causing website downtime, loss of access to critical web services, and reputational damage. This is particularly impactful for organizations relying on Concrete CMS for customer-facing portals, e-commerce, or internal communication platforms. The requirement for some level of privileges to exploit the vulnerability suggests that insider threats or compromised accounts could be leveraged to trigger the DoS. Given the high availability impact, organizations with strict uptime requirements or those providing essential services could face operational disruptions. While confidentiality and integrity are not directly affected, the unavailability of services can indirectly impact business continuity and user trust.

Organizations should prioritize upgrading Concrete CMS installations to versions above 8.5.10 or beyond 9.1.2 where this vulnerability is addressed. In the absence of official patches, administrators should implement strict access controls to limit authenticated user privileges, minimizing the risk of exploitation by low-privilege accounts. Monitoring and alerting on unusual growth or saturation of the authTypeConcreteCookieMap table or related resource usage can provide early detection of exploitation attempts. Rate limiting authenticated requests and implementing web application firewalls (WAFs) with custom rules to detect and block suspicious patterns targeting the authTypeConcreteCookieMap resource can reduce attack surface. Additionally, regular audits of user accounts and session management policies should be enforced to prevent unauthorized access. For high-value targets, deploying resource usage quotas or isolation mechanisms at the database or application layer can prevent resource exhaustion. Finally, organizations should maintain incident response plans that include DoS scenarios related to CMS vulnerabilities.