CVE-2025-12815 is a vulnerability classified under CWE-283 (Unverified Ownership) affecting AWS Research and Engineering Studio (RES) versions before 2025.09. The flaw resides in the Virtual Desktop preview page, where the system fails to properly verify ownership of desktop session metadata. As a result, an authenticated remote user can view metadata and periodic screenshots of another user's active desktop session without authorization. This exposure could reveal sensitive information displayed or processed during the session, potentially leading to privacy breaches or leakage of proprietary data. The vulnerability does not require user interaction and can be exploited remotely with low attack complexity, but it does require the attacker to have valid credentials (authenticated access). The CVSS 4.0 vector indicates network attack vector (AV:N), low attack complexity (AC:L), no privileges required beyond authentication (PR:L), no user interaction (UI:N), and no impact on integrity or availability, only confidentiality (VC:N, VI:N, VA:N). AWS has released version 2025.09 to address this issue, and users are advised to upgrade promptly. No public exploits or active exploitation have been reported to date.

For European organizations, this vulnerability poses a risk of unauthorized disclosure of sensitive session data within AWS RES environments. Organizations involved in research, engineering, or any domain relying on virtual desktop infrastructure hosted on AWS RES could have confidential project data or intellectual property exposed to unauthorized users within the same environment. This could lead to competitive disadvantage, regulatory compliance issues (especially under GDPR if personal data is involved), and reputational damage. Since the vulnerability requires authenticated access, insider threats or compromised credentials are the primary risk vectors. The impact is primarily on confidentiality, with no direct effect on system integrity or availability. The medium severity rating reflects a moderate risk that can be mitigated by timely patching and access control measures.

The primary mitigation is to upgrade AWS Research and Engineering Studio to version 2025.09 or later, where the ownership verification issue is fixed. Beyond patching, organizations should enforce strict access controls and least privilege principles for RES users to minimize the risk of credential misuse. Implement multi-factor authentication (MFA) to reduce the risk of compromised credentials. Regularly audit and monitor RES access logs for unusual or unauthorized access patterns. Segregate RES environments where possible to limit lateral movement. Educate users about credential security and insider threat risks. If upgrading immediately is not feasible, consider disabling the Virtual Desktop preview feature or restricting it to trusted users only until the patch can be applied.