CVE-2025-67364
Efforthye Fast-Filesystem-Mcp 3.4.0
Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:NSummary
CVE-2025-67364 is a high-severity Path Traversal: '../filedir' (CWE-24) vulnerability in Efforthye Fast-Filesystem-Mcp. Its CVSS base score is 7.5 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Data from Local System (T1005); ranked at the 45th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
This vulnerability is AI-related — categorised as AI Agent Protocols and Integrations; in the Protocol-Specific Risks risk domain.
The strongest mitigations our analysis identified map to SI-10 (Information Input Validation) and AC-3 (Access Enforcement) — see the control section below for these in your framework.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
CVE-2025-67364 is a path traversal vulnerability (CWE-24) in fast-filesystem-mcp version 3.4.0, affecting its file operation tools including fast_read_file. The issue stems from improper path validation in the safePath and isPathAllowed functions, which use path.resolve() without resolving symbolic links to their actual physical paths. This flaw enables attackers to bypass directory access restrictions by creating symlinks within allowed directories that point to restricted system paths.
Unauthenticated remote attackers can exploit this vulnerability over the network with low attack complexity and no user interaction required. By placing symlinks in permitted directories that reference sensitive files, attackers can access them via valid path references, evading validation checks and obtaining unauthorized file contents. The CVSS v3.1 base score is 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N), reflecting high confidentiality impact with no integrity or availability disruption.
Mitigation details and advisories are available in the project repository at https://github.com/efforthye/fast-filesystem-mcp and the related issue tracker at https://github.com/efforthye/fast-filesystem-mcp/issues/10, published on 2026-01-07.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-1195
Vulnerability Data
fast-filesystem-mcp version 3.4.0 contains a critical path traversal vulnerability in its file operation tools including fast_read_file. This vulnerability arises from improper path validation that fails to resolve symbolic links to their actual physical paths. The safePath and isPathAllowed functions use…
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path.resolve() which does not handle symlinks, allowing attackers to bypass directory access restrictions by creating symlinks within allowed directories that point to restricted system paths. When these symlinks are accessed through valid path references, the validation checks are circumvented, enabling access to unauthorized files.
- CWE(s)
AI Security AnalysisAI
- AI Category
- AI Agent Protocols and Integrations
- Risk Domain
- Protocol-Specific Risks
- OWASP Top 10 for LLMs 2025
- None mapped
- Classification Reason
- Matched keywords: mcp
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Input validation directly neutralizes '../' sequences in externally-supplied pathnames before they are resolved.
Enforced access authorizations can limit the damage even when path traversal succeeds.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Secure SDLC practices directly require input validation and path sanitization that prevent ../ traversal.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Secure coding standards require neutralizing ../ sequences and canonicalizing paths before file operations.
Security testing in development catches path-traversal flaws before release.
Secure SDLC mandates input validation and path canonicalization that directly block ../ traversal.
Application security requirements explicitly call for controls against path traversal in file-handling functions.
Secure architecture principles reduce attack surface but do not prescribe the specific coding fix.
Information access restriction limits which files can be reached, mitigating impact of traversal.