CVE-2025-54107 is a vulnerability categorized under CWE-41 (Improper Resolution of Path Equivalence) affecting Microsoft Windows 10 Version 1507 (build 10.0.10240.0). The issue resides in the MapUrlToZone function, which is responsible for mapping URLs to security zones in Windows. Due to improper handling of path equivalence, an attacker can craft URLs that bypass security zone checks, effectively circumventing security features designed to restrict or control content based on zone classification. This vulnerability can be exploited remotely over a network without requiring privileges, although user interaction is necessary to trigger the exploit. The CVSS v3.1 base score is 4.3, reflecting a medium severity level, with impact limited to confidentiality (partial information disclosure or bypass of security controls) and no direct impact on integrity or availability. The attack complexity is low, and no authentication is required, but user interaction (e.g., clicking a malicious link) is needed. No known exploits have been reported in the wild, and no official patches have been released as of the publication date. The vulnerability primarily affects legacy Windows 10 installations, which may still be in use in some environments despite being out of mainstream support. The flaw could be leveraged as a stepping stone for further attacks by bypassing security zone restrictions that normally help isolate potentially harmful content.

The primary impact of CVE-2025-54107 is the bypass of security zone restrictions in Windows 10 Version 1507, which can lead to unauthorized access to content or resources that would otherwise be blocked or restricted. This may result in partial disclosure of sensitive information or exposure to malicious content that security zones are designed to contain. While the vulnerability does not directly compromise system integrity or availability, the security feature bypass can facilitate subsequent attacks such as phishing, drive-by downloads, or execution of malicious scripts under less restrictive conditions. Organizations running this outdated Windows version may face increased risk of targeted attacks exploiting this flaw, especially in environments where users frequently interact with external URLs or network resources. The lack of patches and the requirement for user interaction somewhat limit the scope, but the low complexity and no privilege requirement make it a notable risk. The vulnerability could be particularly impactful in sectors with legacy systems and high-value targets, where attackers seek to circumvent layered defenses.

1. Upgrade affected systems to a supported and fully patched version of Windows 10 or later to eliminate the vulnerability entirely. 2. Restrict network exposure of legacy Windows 10 Version 1507 systems by segmenting them from the internet and untrusted networks. 3. Implement strict URL filtering and web content filtering to block potentially malicious or crafted URLs that could exploit the path equivalence issue. 4. Educate users to avoid clicking on suspicious links or opening untrusted URLs, as user interaction is required for exploitation. 5. Employ endpoint detection and response (EDR) solutions to monitor for unusual URL access patterns or attempts to bypass security zones. 6. Use application whitelisting and browser security features to limit execution of unauthorized scripts or code. 7. Regularly audit and inventory legacy systems to prioritize remediation and reduce attack surface. 8. Monitor threat intelligence feeds for any emerging exploits or patches related to this CVE.