{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "fixed": "5.1.0"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "b4ee96dac799cbfba0a9f9c17844ce9d613cbcc7"
            },
            {
              "fixed": "94815a16e3322101694e97561fc1dc8b5af904dc"
            }
          ],
          "repo": "https://github.com/ooples/token-optimizer-mcp",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-49mq-fc6q-3h46"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-78"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/55xxx/CVE-2026-55157.json"
  },
  "details": "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, token-optimizer-mcp is vulnerable to OS command injection in the smart_user tool. Any MCP client that can call the smart_user tool can execute arbitrary shell commands through the username argument of the get-user-info operation. The commands execute with the privileges of the user running the token-optimizer-mcp server. This issue has been patched in version 5.1.0.",
  "id": "CVE-2026-55157",
  "modified": "2026-10-02T03:30:24.383785005Z",
  "published": "2026-09-28T17:48:16.422Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/ooples/token-optimizer-mcp/releases/tag/v5.1.0"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/55xxx/CVE-2026-55157.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/ooples/token-optimizer-mcp/security/advisories/GHSA-49mq-fc6q-3h46"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-55157"
    },
    {
      "type": "FIX",
      "url": "https://github.com/ooples/token-optimizer-mcp/commit/b4ee96dac799cbfba0a9f9c17844ce9d613cbcc7"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Token Optimizer MCP: OS command injection in smart_user via username in get-user-info"
}