PYSEC-2026-2623

Vulnerability from pysec - Published: 2026-07-13 14:36 - Updated: 2026-07-13 16:04
VLAI
Details

Summary

The /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.

Details

Vulnerable Code

health.py:90-101 - System information collection

system_info = {
    "platform": platform.system(),              # e.g., "Linux", "Darwin"
    "platform_version": platform.version(),     # Full OS kernel version string
    "python_version": platform.python_version(),# e.g., "3.12.1"
    "cpu_count": psutil.cpu_count(),            # CPU core count
    "memory_total_gb": round(memory_info.total / (1024**3), 2),
    "memory_available_gb": round(memory_info.available / (1024**3), 2),
    "memory_percent": memory_info.percent,
    "disk_total_gb": round(disk_info.total / (1024**3), 2),
    "disk_free_gb": round(disk_info.free / (1024**3), 2),
    "disk_percent": round((disk_info.used / disk_info.total) * 100, 2)
}

health.py:131-132 - Database path disclosure

if hasattr(storage, 'db_path'):
    storage_info["database_path"] = storage.db_path  # Full filesystem path

Authentication Bypass Path

The /api/health/detailed endpoint uses require_read_access which calls get_current_user. When MCP_ALLOW_ANONYMOUS_ACCESS=true, the auth middleware grants access:

# middleware.py:372-379
if ALLOW_ANONYMOUS_ACCESS:
    logger.debug("Anonymous access explicitly enabled, granting read-only access")
    return AuthenticationResult(
        authenticated=True,
        client_id="anonymous",
        scope="read",
        auth_method="none"
    )

Note: The basic /health endpoint (line 68) has no auth dependency at all and returns version and uptime information unconditionally.

Information Exposed

Field Example Value Reconnaissance Value
platform "Linux" OS fingerprinting
platform_version "#1 SMP PREEMPT_DYNAMIC..." Kernel version → CVE targeting
python_version "3.12.1" Python CVE targeting
cpu_count 8 Resource enumeration
memory_total_gb 32.0 Infrastructure profiling
database_path "/home/user/.mcp-memory/memories.db" Username + file path disclosure
database_size_mb 45.2 Data volume estimation

Attack Scenario

  1. Attacker scans the local network for services on port 8000
  2. Finds mcp-memory-service with HTTP enabled and anonymous access
  3. Calls GET /api/health/detailed (no credentials needed)
  4. Receives OS version, Python version, full database path (revealing username), system resources
  5. Uses this information to:
  6. Target known CVEs for the specific OS/Python version
  7. Identify the database file location for potential direct access
  8. Profile the system for further attacks

PoC

# Show the system info that would be exposed
import platform, psutil

system_info = {
    "platform": platform.system(),
    "platform_version": platform.version(),
    "python_version": platform.python_version(),
    "cpu_count": psutil.cpu_count(),
    "memory_total_gb": round(psutil.virtual_memory().total / (1024**3), 2),
}
print(system_info)  # All of this is returned to unauthenticated users

Impact

  • OS fingerprinting: Exact OS and kernel version enables targeted exploit selection
  • Path disclosure: Database path reveals username, home directory structure, and file locations
  • Resource enumeration: CPU, memory, and disk info reveal infrastructure scale
  • Reconnaissance enablement: Combined information significantly reduces attacker effort for follow-up attacks

Remediation

  1. Remove system details from default health endpoint - return only status, version, uptime:
@router.get("/health/detailed")
async def detailed_health_check(
    storage: MemoryStorage = Depends(get_storage),
    user: AuthenticationResult = Depends(require_write_access)  # Require admin/write access
):
    # Only return storage stats, not system info
    ...
  1. Do not expose database_path - this leaks the filesystem structure:
# Remove or redact
# storage_info["database_path"] = storage.db_path  # REMOVE THIS
  1. Add auth to basic /health or limit it to status-only (no version):
@router.get("/health")
async def health_check():
    return {"status": "healthy"}  # No version, no uptime

Alternatively, Bind to 127.0.0.1 by default instead of 0.0.0.0, preventing network-based reconnaissance entirely:

# In config.py — change default from '0.0.0.0' to '127.0.0.1'
HTTP_HOST = os.getenv('MCP_HTTP_HOST', '127.0.0.1')

Users 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
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Impacted products
Name purl
mcp-memory-service pkg:pypi/mcp-memory-service
Aliases
To clipboard 

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "mcp-memory-service",
        "purl": "pkg:pypi/mcp-memory-service"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "10.21.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "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"
      ]
    }
  ],
  "aliases": [
    "CVE-2026-29787",
    "GHSA-73hc-m4hx-79pj"
  ],
  "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, \u0027db_path\u0027):\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 \u2192 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 \u2014 change default from \u00270.0.0.0\u0027 to \u0027127.0.0.1\u0027\nHTTP_HOST = os.getenv(\u0027MCP_HTTP_HOST\u0027, \u0027127.0.0.1\u0027)\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.",
  "id": "PYSEC-2026-2623",
  "modified": "2026-07-13T16:04:48.777953Z",
  "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"
    }
  ],
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "mcp-memory-service Vulnerable to System Information Disclosure via Health Endpoint"
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.