CVE-2025-55325 is a buffer over-read vulnerability classified under CWE-126, affecting the Windows Storage Management Provider in Microsoft Windows 11 Version 25H2 (build 10.0.26200.0). The vulnerability arises when the component improperly handles memory boundaries, allowing an attacker with authorized local access and low privileges to read beyond intended memory buffers. This can lead to disclosure of sensitive information residing in memory, such as cryptographic keys, passwords, or other confidential data. The attack vector requires local access (AV:L) and low complexity (AC:L), with privileges required (PR:L) but no user interaction (UI:N). The scope is unchanged (S:U), meaning the impact is confined to the vulnerable component and does not extend to other system components. The CVSS v3.1 base score is 5.5, indicating medium severity, with a high impact on confidentiality (C:H), but no impact on integrity (I:N) or availability (A:N). No known exploits have been reported in the wild, and no patches have been released at the time of publication. The vulnerability was reserved in August 2025 and published in October 2025. The lack of patches necessitates proactive mitigation steps. This vulnerability is significant because it can expose sensitive information to local attackers, which could be leveraged in further attacks or lateral movement within a network.

For European organizations, the primary impact of CVE-2025-55325 is the potential unauthorized disclosure of sensitive information stored in memory on Windows 11 25H2 systems. This could compromise confidentiality of critical data, including credentials or cryptographic material, potentially facilitating further attacks such as privilege escalation or lateral movement. Sectors handling sensitive personal data (e.g., healthcare, finance, government) are particularly at risk due to regulatory requirements like GDPR. Since exploitation requires local access and some privileges, insider threats or attackers who have already gained limited footholds pose the greatest risk. The vulnerability does not affect system integrity or availability, so direct disruption is unlikely. However, information disclosure can undermine trust and lead to compliance violations. The absence of known exploits reduces immediate risk but does not eliminate it, especially as attackers may develop exploits once patches are released. Organizations relying heavily on Windows 11 25H2 in critical infrastructure or enterprise environments should prioritize mitigation to prevent data leakage.

1. Apply official Microsoft patches immediately once they become available to address CVE-2025-55325. 2. Until patches are released, restrict local access to Windows 11 25H2 systems by enforcing strict access controls and limiting user privileges to the minimum necessary. 3. Implement robust endpoint detection and response (EDR) solutions to monitor for suspicious local activities indicative of exploitation attempts. 4. Conduct regular audits of user accounts and permissions to identify and remove unnecessary privileges that could be leveraged by attackers. 5. Use application whitelisting and device control policies to prevent unauthorized software execution and lateral movement. 6. Educate users about the risks of local attacks and enforce policies to prevent unauthorized physical or remote access to endpoints. 7. Employ memory protection technologies such as Data Execution Prevention (DEP) and Address Space Layout Randomization (ASLR) to reduce exploitation likelihood. 8. Maintain up-to-date backups and incident response plans to quickly recover if an information disclosure incident occurs. 9. Monitor security advisories from Microsoft and threat intelligence sources for updates on exploit developments and mitigation guidance.