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The security vulnerability tracked under CVE-2025-68145 represents a critical flaw residing within the configuration loading mechanism and path handling components of Model Context Protocol (MCP) server implementations.
Specifically, when an MCP server parses environment variables, project-local configuration files, or command-line arguments without rigorous sanitization, it exposes the underlying host filesystem to untrusted inputs.
In older versions of affected software, the config loader fails to canonicalize or validate repository and file paths correctly across different operating systems.
When attackers supply specially crafted input containing directory traversal sequences such as dot-dot-slash or Windows-style backslash separators, the application resolves these paths relative to the root directory without proper boundary enforcement.
This architectural oversight allows a malicious or compromised project directory to override default configuration parameters, steering file read and write operations outside the intended secure sandbox.
The root cause stems from the lack of strict path validation during the initial configuration parsing phase, where user-controlled strings are directly concatenated into file system operations.
Consequently, when automated tools or AI agents execute workspace operations, they unknowingly process these poisoned paths, leading to arbitrary file access or system compromise.
Remediation requires enforcing strict path canonicalization, validating all inputs against allowed base directories, and removing unsafe default fallback behaviors in the config loader.
DailyCVE Form:
Platform: cve-search_mcp
Version: Below 4.63
Vulnerability: Path traversal
Severity: Critical
date: 2026-10-14
Prediction: Already patched
What Undercode Say:
Undercode analyzed the release patch and noted that the fix addresses improper path resolution in the config loader. Here are the relevant diagnostic and verification bash commands used during the audit:
git clone https://github.com/ThomasAhmed/cve-search_mcp.git cd cve-search_mcp uv sync --extra dev python -m pytest tests/test_config.py git log -p -n 1 -- src/config.py
The code fix implements path canonicalization using standard library modules to ensure all configuration paths remain strictly within the designated workspace boundary.
Exploit: (Educational Purposes!)
To demonstrate the vulnerability conceptually in a controlled laboratory environment, an attacker crafts a malicious configuration file that injects directory traversal sequences into path-handling variables:
{
"mcpServers": {
"cve-search": {
"command": "python",
"args": ["main.py"],
"env": {
"CONFIG_PATH": "../../../etc/passwd"
}
}
}
}
When the unpatched config loader parses this environment payload without validation, it traverses out of the intended directory structure and exposes sensitive host files to the executing MCP client.
Protection: from this CVE
To protect systems against this vulnerability, administrators and developers must immediately take the following remediation steps:
Update the cve-search_mcp package to version 4.63.822 or higher where windows paths and config loaders are secured.
Implement strict path validation and canonicalization checks before processing any user-supplied or project-local configuration files.
Restrict MCP server execution permissions and isolate server processes within dedicated sandboxed environments or containers.
Impact:
Successful exploitation of this vulnerability can result in severe security consequences, including unauthorized read and write access to sensitive host files, potential disclosure of environment secrets or API keys, and complete compromise of the local development environment or server integrity.
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Sources:
Reported By: github.com
Extra Source Hub:
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