CVE-2025-53110 is a high-severity vulnerability classified under CWE-22, which pertains to improper limitation of a pathname to a restricted directory, commonly known as a path traversal vulnerability. This vulnerability affects the Model Context Protocol (MCP) servers, specifically versions of the Filesystem component prior to 0.6.4 or 2025.7.01. The MCP servers are reference implementations designed to handle model context protocols, and the Filesystem component manages file access within these servers. The vulnerability arises when the server incorrectly validates file path prefixes, allowing an attacker to craft a pathname that bypasses directory restrictions. This can lead to unauthorized access to files outside the intended directories, potentially exposing sensitive data or configuration files. The CVSS 4.0 base score of 7.3 reflects a high severity, with an attack vector of network (AV:N), low attack complexity (AC:L), no privileges required (PR:N), but requiring user interaction (UI:P). The vulnerability does not impact confidentiality or integrity directly (VC:N, VI:N), but has a high impact on availability (VA:H), scope (S:H), and security requirements for integrity and availability (SI:H, SA:H). Although no known exploits are currently reported in the wild, the nature of path traversal vulnerabilities makes them attractive targets for attackers aiming to escalate access or gather sensitive information. The recommended remediation is to upgrade to versions 0.6.4 or 2025.7.01 of the Filesystem component, where this issue has been resolved.

For European organizations utilizing MCP servers, this vulnerability poses a significant risk. Unauthorized file access can lead to exposure of sensitive corporate data, intellectual property, or personally identifiable information (PII), which is particularly critical under the GDPR framework. The ability to access unintended files may also allow attackers to manipulate configuration files or logs, potentially disrupting service availability or enabling further attacks such as privilege escalation or lateral movement within networks. Given the network attack vector and no requirement for privileges, attackers can exploit this vulnerability remotely, increasing the risk of widespread impact. The high availability impact suggests potential for denial-of-service conditions if critical files are accessed or corrupted. Organizations in sectors such as finance, healthcare, and critical infrastructure, which often deploy MCP servers or similar protocols, may face operational disruptions and regulatory penalties if exploited.

European organizations should immediately verify their MCP server versions and upgrade the Filesystem component to version 0.6.4 or 2025.7.01 or later. Beyond patching, organizations should implement strict input validation and sanitization on all file path inputs to ensure that path traversal sequences (e.g., '../') are properly handled or rejected. Employing application-layer firewalls or intrusion detection systems with rules to detect anomalous file access patterns can provide additional protection. Access controls should be reviewed and tightened to limit file system permissions to the minimum necessary for MCP server operation, reducing the impact of any potential exploitation. Regular security audits and code reviews focusing on file handling routines can help identify similar vulnerabilities proactively. Finally, monitoring logs for unusual file access attempts and user interactions can facilitate early detection of exploitation attempts.