sublinear-time-solver consciousness-explorer Arbitrary File Write Vulnerability (CWE-73) Analysis

Vulnerability Overview An arbitrary file write vulnerability (CWE-73) was discovered in the component of . This vulnerability allows an attacker to write to or overwrite arbitrary files accessible by the server process via the MCP interface, resulting in data loss and potential service disruption. Scope of Impact Affected Versions: , , commit Security Impact: - Confidentiality: Unconfirmed - Integrity: High (the attacker can write to or overwrite files) - Availability: High (the attacker can overwrite application files, user files, or other writable targets) - Scope: Unchanged Remediation Steps 1. Do not accept arbitrary output paths for 2. Store exported states in a dedicated, application-controlled directory 3. If the caller can select the filename, accept only the filename and reject path separators, absolute paths, segments, symbolic links, and reserved device names 4. Resolve the final path and verify that it remains within the expected export directory 5. Use secure file creation flags where appropriate to avoid accidental overwriting of existing files 6. Add regression tests demonstrating that absolute path and traversal payloads cannot write outside the expected directory 7. Publish a security advisory for maintainers after the patch release POC Code Verification Steps 1. Start the MCP server via without modifying the repository code, for example, by using to import the existing class and call . 2. Invoke the tool with the parameters above. 3. Confirm that is created by the MCP server process. 4. Inspect the file and verify it contains the exported JSON state data. 5. Manually confirm via that the control file is written through the parameter. Technical Root Cause Source: ( tool) Source Parameter: ( ) Source-to-Sink Taint: Sink: Sink Code: Attack Preconditions The attacker can invoke the MCP tool. The MCP server process has file system write permissions to the destination chosen by the attacker. There is no effective runtime policy restricting to a dedicated state directory or rejecting absolute/traversal paths. The write operation occurs with the privileges of the MCP server process. CVSS v3.1 Recommendations Recommended Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H Recommended Base Score: 7.1 (High) Adjust AV to H: If the affected MCP tool is exposed via a remotely accessible MCP bridge or service Workarounds / Mitigations Until a fix is available, do not expose the MCP server to untrusted clients. Restrict access to the tool to trusted local users only. Run the MCP server using a dedicated low-privilege OS account and a restricted working directory. Configure file system permissions so the MCP process cannot write to sensitive locations. References Repository: https://github.com/numnet/sublinear-time-solver Audited Source Files: - - CWE-73: https://cwe.mitre.org/data/definitions/73.html Credits Discoverer: BruceJin Discovery Method: Static analysis (CodeQL), repository source code audit, and manual reproduction with Additional Notes Audit Conclusion: Manual reproduction confirmed that attacker-controlled MCP reaches a file system write sink and creates files in any process-accessible path. Dynamic Replay Status: Completed using with : confirmed successful tool execution, and the output file was observed locally. Maintainers should verify the published mapping before coordinated disclosure.

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sublinear-time-solver consciousness-explorer Arbitrary File Write Vulnerability (CWE-73) Analysis

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