CVE-2025-4962 is a high-severity vulnerability classified under CWE-284 (Improper Access Control) affecting the lunary-ai/lunary product, specifically versions up to 0.8.8. The vulnerability resides in the API endpoint `POST /v1/templates`, where authenticated users can create templates within projects they do not own by manipulating the `projectId` query parameter. This is a classic Insecure Direct Object Reference (IDOR) flaw, where the server fails to verify ownership or authorization of the resource referenced by the user-supplied identifier. The root cause is the lack of server-side validation to confirm that the authenticated user has rights over the specified `projectId`. Because of this, an attacker with valid credentials can escalate privileges within the application by injecting templates into other users' projects, potentially disrupting workflows or injecting malicious content. The vulnerability does not require user interaction beyond authentication and can be exploited remotely over the network, as indicated by the CVSS vector (AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N). The impact primarily affects the integrity of project data, as unauthorized template creation can alter project contents without detection. Confidentiality and availability are not directly impacted. The vulnerability has been fixed in version 1.9.23 of lunary-ai/lunary. No known exploits are currently reported in the wild, but the ease of exploitation and high impact on integrity make this a significant risk if left unpatched.

For European organizations using lunary-ai/lunary, this vulnerability poses a significant risk to project data integrity. Unauthorized template creation could lead to data corruption, insertion of malicious templates, or disruption of legitimate workflows, potentially causing operational delays or erroneous outputs. Organizations relying on lunary for critical project management or AI template generation may face internal data integrity issues, undermining trust in the platform. Although confidentiality is not directly compromised, the ability to alter project contents without authorization can have cascading effects on decision-making and compliance, especially in regulated industries such as finance, healthcare, and government sectors prevalent in Europe. The vulnerability requires authenticated access, so insider threats or compromised credentials increase risk. Given the collaborative nature of many European enterprises and the potential for cross-team project sharing, this flaw could be exploited to affect multiple users or departments. The lack of known exploits in the wild provides a window for mitigation, but the high CVSS score indicates that exploitation could have serious consequences if attackers gain access.

European organizations should immediately upgrade lunary-ai/lunary installations to version 1.9.23 or later, where the vulnerability is patched. Until upgrades are possible, implement strict access controls and monitoring on API usage, particularly the `POST /v1/templates` endpoint, to detect anomalous projectId modifications. Enforce least privilege principles to limit user permissions to only projects they own or manage. Conduct thorough audits of project ownership and template creation logs to identify unauthorized activities. Integrate multi-factor authentication (MFA) to reduce risks from compromised credentials. Additionally, implement Web Application Firewall (WAF) rules to detect and block suspicious API requests that attempt to manipulate projectId parameters. Educate users about the risks of credential sharing and monitor for insider threat indicators. Finally, coordinate with lunary-ai support for any additional security advisories and best practices.