CVE-2026-29787: Mcp memory service Mcp-memory-service Vulnerable To System Information Vulnerability

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-73hc-m4hx-79pj",
  "modified" : "2026-03-09T15:50:08Z",
  "published" : "2026-03-05T21:42:10Z",
  "aliases" : [ "CVE-2026-29787" ],
  "summary" : "mcp-memory-service Vulnerable to System Information Disclosure via Health Endpoint",
  "details" : "### Summary\nThe `/api/health/detailed` endpoint returns detailed system information including OS version, Python version, CPU count, memory totals, disk usage, and the full database filesystem path. When `MCP_ALLOW_ANONYMOUS_ACCESS=true` is set (required for the HTTP server to function without OAuth/API key), this endpoint is accessible without authentication. Combined with the default `0.0.0.0` binding, this exposes sensitive reconnaissance data to the entire network.\n\n### Details\n### Vulnerable Code\n\n**`health.py:90-101` - System information collection**\n\n```python\nsystem_info = {\n    \"platform\": platform.system(),              # e.g., \"Linux\", \"Darwin\"\n    \"platform_version\": platform.version(),     # Full OS kernel version string\n    \"python_version\": platform.python_version(),# e.g., \"3.12.1\"\n    \"cpu_count\": psutil.cpu_count(),            # CPU core count\n    \"memory_total_gb\": round(memory_info.total / (1024**3), 2),\n    \"memory_available_gb\": round(memory_info.available / (1024**3), 2),\n    \"memory_percent\": memory_info.percent,\n    \"disk_total_gb\": round(disk_info.total / (1024**3), 2),\n    \"disk_free_gb\": round(disk_info.free / (1024**3), 2),\n    \"disk_percent\": round((disk_info.used / disk_info.total) * 100, 2)\n}\n```\n\n**`health.py:131-132` - Database path disclosure**\n\n```python\nif hasattr(storage, 'db_path'):\n    storage_info[\"database_path\"] = storage.db_path  # Full filesystem path\n```\n\n### Authentication Bypass Path\n\nThe `/api/health/detailed` endpoint uses `require_read_access` which calls `get_current_user`. When `MCP_ALLOW_ANONYMOUS_ACCESS=true`, the auth middleware grants access:\n\n```python\n# middleware.py:372-379\nif ALLOW_ANONYMOUS_ACCESS:\n    logger.debug(\"Anonymous access explicitly enabled, granting read-only access\")\n    return AuthenticationResult(\n        authenticated=True,\n        client_id=\"anonymous\",\n        scope=\"read\",\n        auth_method=\"none\"\n    )\n```\n\n**Note**: The basic `/health` endpoint (line 68) has **no auth dependency at all** and returns version and uptime information unconditionally.\n\n### Information Exposed\n\n| Field | Example Value | Reconnaissance Value |\n|-------|--------------|---------------------|\n| `platform` | `\"Linux\"` | OS fingerprinting |\n| `platform_version` | `\"#1 SMP PREEMPT_DYNAMIC...\"` | Kernel version → CVE targeting |\n| `python_version` | `\"3.12.1\"` | Python CVE targeting |\n| `cpu_count` | `8` | Resource enumeration |\n| `memory_total_gb` | `32.0` | Infrastructure profiling |\n| `database_path` | `\"/home/user/.mcp-memory/memories.db\"` | Username + file path disclosure |\n| `database_size_mb` | `45.2` | Data volume estimation |\n\n### Attack Scenario\n\n1. Attacker scans the local network for services on port 8000\n2. Finds mcp-memory-service with HTTP enabled and anonymous access\n3. Calls `GET /api/health/detailed`  (no credentials needed)\n4. Receives OS version, Python version, full database path (revealing username), system resources\n5. Uses this information to:\n   - Target known CVEs for the specific OS/Python version\n   - Identify the database file location for potential direct access\n   - Profile the system for further attacks\n \n### PoC\n\n```python\n# Show the system info that would be exposed\nimport platform, psutil\n\nsystem_info = {\n    \"platform\": platform.system(),\n    \"platform_version\": platform.version(),\n    \"python_version\": platform.python_version(),\n    \"cpu_count\": psutil.cpu_count(),\n    \"memory_total_gb\": round(psutil.virtual_memory().total / (1024**3), 2),\n}\nprint(system_info)  # All of this is returned to unauthenticated users\n```\n\n### Impact\n- **OS fingerprinting**: Exact OS and kernel version enables targeted exploit selection\n- **Path disclosure**: Database path reveals username, home directory structure, and file locations\n- **Resource enumeration**: CPU, memory, and disk info reveal infrastructure scale\n- **Reconnaissance enablement**: Combined information significantly reduces attacker effort for follow-up attacks\n\n## Remediation\n\n1. **Remove system details from default health endpoint** - return only `status`, `version`, `uptime`:\n\n```python\n@router.get(\"/health/detailed\")\nasync def detailed_health_check(\n    storage: MemoryStorage = Depends(get_storage),\n    user: AuthenticationResult = Depends(require_write_access)  # Require admin/write access\n):\n    # Only return storage stats, not system info\n    ...\n```\n\n2. **Do not expose `database_path`** - this leaks the filesystem structure:\n\n```python\n# Remove or redact\n# storage_info[\"database_path\"] = storage.db_path  # REMOVE THIS\n```\n\n3. **Add auth to basic `/health`** or limit it to status-only (no version):\n\n```python\n@router.get(\"/health\")\nasync def health_check():\n    return {\"status\": \"healthy\"}  # No version, no uptime\n```\nAlternatively, **Bind to `127.0.0.1` by default** instead of `0.0.0.0`, preventing network-based reconnaissance entirely:\n\n```python\n# In config.py — change default from '0.0.0.0' to '127.0.0.1'\nHTTP_HOST = os.getenv('MCP_HTTP_HOST', '127.0.0.1')\n```\n\nUsers who need network access can explicitly set `MCP_HTTP_HOST=0.0.0.0`, making the exposure a conscious opt-in rather than a default.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "mcp-memory-service"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "10.21.0"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/doobidoo/mcp-memory-service/security/advisories/GHSA-73hc-m4hx-79pj"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-29787"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/doobidoo/mcp-memory-service/commit/18f4323ca92763196aa2922f691dfbeb6bd84e48"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/doobidoo/mcp-memory-service"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-200" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-03-05T21:42:10Z",
    "nvd_published_at" : "2026-03-07T16:15:55Z"
  }
}