CVE Catalog

CVE-2026-79534

MediumCVSS 5.9
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.19%

8th percentile - higher than 8% of all known CVEs

Summary

Directory Traversal vulnerability in mcp-filesystem-server v0.11.1 due to improper link resolution in validatePath. When EvalSymlinks returns os.IsNotExist for a dangling symlink, the fallback validates only the parent directory and returns the unresolved path, allowing file writes outside allowed directories.

Risk Assessment

An attacker can write, modify, or copy files outside allowed directories, leading to filesystem integrity compromise.

Recommendation

Update mcp-filesystem-server to the latest version and fix path validation logic.

Related vulnerabilities

Original NVD description (English source)

mark3labs mcp-filesystem-server v0.11.1 is vulnerable to Directory Traversal due to an improper link resolution in validatePath (filesystemserver/handler/helper.go). When filepath.EvalSymlinks returns os.IsNotExist for a dangling symlink, the fallback validates only the parent directory and returns the unresolved path, so write_file (and modify_file, copy_file, move_file, create_directory) follows a pre-existing dangling symlink located inside an allowed directory and creates a file outside the configured allowed directories.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS