CVE-2025-55247 is a vulnerability classified under CWE-59 (Improper Link Resolution Before File Access) affecting Microsoft .NET 8.0, specifically version 8.0.0. The flaw arises from the improper handling of symbolic links or junction points before accessing files, which can be exploited by an authorized local attacker to perform privilege escalation. This 'link following' issue means that when the .NET runtime or associated libraries resolve file paths, they may follow symbolic links incorrectly, allowing an attacker to redirect file operations to unintended locations. As a result, the attacker can gain elevated privileges by manipulating file access controls, potentially overwriting or reading sensitive files that should be protected. The CVSS 3.1 score of 7.3 reflects a high severity, with attack vector being local (AV:L), requiring low attack complexity (AC:L), and limited privileges (PR:L). User interaction is required (UI:R), and the scope is unchanged (S:U). The impact on confidentiality, integrity, and availability is high (C:H/I:H/A:H), indicating that successful exploitation could lead to full system compromise or data breaches. No known exploits are currently in the wild, but the vulnerability was reserved in August 2025 and published in October 2025, suggesting recent discovery. The lack of available patches at the time of reporting means organizations must rely on interim mitigations. This vulnerability is particularly relevant for environments where .NET 8.0 is used for application development or hosting, especially on Windows systems where symbolic links are common. Attackers with local access could leverage this to escalate privileges and compromise systems.

For European organizations, the impact of CVE-2025-55247 can be significant, especially for enterprises relying on Microsoft .NET 8.0 for critical applications and services. Privilege escalation vulnerabilities enable attackers to bypass security controls, potentially leading to unauthorized access to sensitive data, disruption of services, or deployment of further malware. Confidentiality breaches could expose personal data protected under GDPR, leading to regulatory penalties and reputational damage. Integrity and availability impacts could disrupt business operations, particularly in sectors like finance, healthcare, and government where .NET applications are prevalent. Since exploitation requires local access and some user interaction, insider threats or compromised user accounts pose a higher risk. The absence of known exploits currently provides a window for proactive defense, but the high severity score demands urgent attention. Organizations with extensive Windows and .NET infrastructure may face increased risk of lateral movement and privilege escalation within their networks if this vulnerability is exploited.

1. Monitor Microsoft security advisories closely and apply official patches or updates for .NET 8.0 as soon as they become available. 2. Implement strict local user privilege management by minimizing the number of users with local access and restricting permissions to only what is necessary. 3. Employ application whitelisting and endpoint protection solutions that can detect and block suspicious file system activities, especially those involving symbolic links or junction points. 4. Conduct regular audits of symbolic link usage and file system permissions on critical systems to identify and remediate potential misuse. 5. Educate users about the risks of interacting with untrusted files or links to reduce the likelihood of user interaction facilitating exploitation. 6. Use virtualization or sandboxing techniques for running untrusted or less-trusted applications to contain potential privilege escalation attempts. 7. Implement robust logging and monitoring to detect unusual privilege escalation attempts or anomalous file access patterns. 8. Consider network segmentation to limit the impact of compromised local accounts and reduce lateral movement opportunities.