{"id":"PYSEC-2026-2623","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.","aliases":["CVE-2026-29787","GHSA-73hc-m4hx-79pj"],"modified":"2026-07-13T16:32:13.346736655Z","published":"2026-07-13T14:36:41.095636Z","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"},{"type":"PACKAGE","url":"https://pypi.org/project/mcp-memory-service"},{"type":"ADVISORY","url":"https://github.com/advisories/GHSA-73hc-m4hx-79pj"}],"affected":[{"package":{"name":"mcp-memory-service","ecosystem":"PyPI","purl":"pkg:pypi/mcp-memory-service"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"10.21.0"}]}],"versions":["10.0.0","10.0.1","10.0.2","10.0.3","10.1.0","10.1.1","10.1.2","10.10.0","10.10.1","10.10.2","10.10.3","10.10.4","10.10.5","10.10.6","10.11.0","10.11.1","10.11.2","10.12.0","10.12.1","10.13.0","10.13.1","10.13.2","10.14.0","10.15.0","10.15.1","10.16.0","10.16.1","10.17.0","10.17.10","10.17.12","10.17.13","10.17.14","10.17.15","10.17.16","10.17.2","10.17.3","10.17.4","10.17.5","10.17.6","10.17.7","10.17.8","10.17.9","10.18.0","10.18.1","10.18.2","10.18.3","10.19.0","10.2.0","10.2.1","10.20.0","10.20.1","10.20.2","10.20.4","10.20.5","10.20.6","10.3.0","10.4.0","10.4.1","10.4.2","10.4.3","10.4.4","10.4.5","10.4.6","10.5.0","10.5.1","10.6.0","10.6.1","10.7.0","10.7.1","10.7.2","10.8.0","10.9.0","8.24.0","8.25.1","8.25.2","8.26.0","8.27.0","8.27.1","8.27.2","8.28.0","8.28.1","8.29.0","8.30.0","8.31.0","8.32.0","8.33.0","8.34.0","8.35.0","8.36.0","8.36.1","8.37.0","8.38.0","8.38.1","8.39.0","8.39.1","8.40.0","8.41.0","8.41.1","8.41.2","8.42.0","8.42.1","8.43.0","8.44.0","8.45.0","8.45.1","8.45.2","8.45.3","8.46.0","8.46.1","8.46.2","8.46.3","8.47.0","8.47.1","8.48.0","8.48.1","8.48.2","8.48.3","8.48.4","8.49.0","8.50.0","8.50.1","8.51.0","8.52.0","8.52.1","8.52.2","8.53.0","8.54.0","8.54.1","8.54.2","8.54.3","8.54.4","8.55.0","8.57.1","8.58.0","8.59.0","8.60.0","8.61.0","8.61.1","8.61.2","8.62.0","8.62.1","8.62.10","8.62.11","8.62.12","8.62.13","8.62.2","8.62.3","8.62.4","8.62.5","8.62.6","8.62.7","8.62.8","8.62.9","8.63.0","8.63.1","8.64.0","8.65.0","8.66.0","8.67.0","8.68.0","8.68.1","8.68.2","8.69.0","8.70.0","8.71.0","8.72.0","8.73.0","8.74.0","8.75.0","8.75.1","8.76.0","9.0.0","9.0.1","9.0.2","9.0.3","9.0.4","9.0.5","9.0.6","9.2.0","9.2.1","9.3.1"],"database_specific":{"source":"https://github.com/pypa/advisory-database/blob/main/vulns/mcp-memory-service/PYSEC-2026-2623.yaml"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N"}]}