Token Optimizer MCP measures token savings per AI coding agent, optimizes context, and shares a live local knowledge graph across 16 CLI clients. Prior to version 5.1.0, the dashboard HTTP server in token-optimizer-mcp exposes /api/session-summary and /api/session-events with no authentication middleware — any network-accessible client can reach them without credentials. Both handlers concatenate the caller-supplied sessionId query parameter directly into a filesystem path via path.join, and Node.js normalizes .. segments at resolution time, allowing an unauthenticated attacker to read any .jsonl file reachable from the server's filesystem. This issue has been patched in version 5.1.0.
Advisories
Source ID Title
Github GHSA Github GHSA GHSA-76pc-mqxp-3rq5 Token Optimizer MCP: Unauthenticated Path Traversal in Dashboard Session Log API Endpoints
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Mon, 28 Sep 2026 19:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Mon, 28 Sep 2026 18:00:00 +0000

Type Values Removed Values Added
Description Token Optimizer MCP measures token savings per AI coding agent, optimizes context, and shares a live local knowledge graph across 16 CLI clients. Prior to version 5.1.0, the dashboard HTTP server in token-optimizer-mcp exposes /api/session-summary and /api/session-events with no authentication middleware — any network-accessible client can reach them without credentials. Both handlers concatenate the caller-supplied sessionId query parameter directly into a filesystem path via path.join, and Node.js normalizes .. segments at resolution time, allowing an unauthenticated attacker to read any .jsonl file reachable from the server's filesystem. This issue has been patched in version 5.1.0.
Title Token Optimizer MCP: Unauthenticated Path Traversal in Dashboard Session Log API Endpoints
Weaknesses CWE-22
References
Metrics cvssV3_1

{'score': 5.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N'}


Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-09-28T18:11:38.212Z

Reserved: 2026-06-16T15:13:28.165Z

Link: CVE-2026-55156

cve-icon Vulnrichment

Updated: 2026-09-28T18:11:33.281Z

cve-icon NVD

Status : Received

Published: 2026-09-28T18:17:23.203

Modified: 2026-09-28T19:16:49.743

Link: CVE-2026-55156

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-09-28T19:30:02Z

Weaknesses