diff --git a/paddleocr-js/package-lock.json b/paddleocr-js/package-lock.json
index 1dd3faa7d5e..d9141ce884f 100644
--- a/paddleocr-js/package-lock.json
+++ b/paddleocr-js/package-lock.json
@@ -11,6 +11,9 @@
         "packages/*",
         "apps/*"
       ],
+      "dependencies": {
+        "protobufjs": "^7.5.5"
+      },
       "devDependencies": {
         "@eslint/js": "^10.0.1",
         "@vitest/coverage-v8": "^3.2.4",
@@ -3891,9 +3894,9 @@
       }
     },
     "node_modules/protobufjs": {
-      "version": "7.5.4",
-      "resolved": "https://registry.npmjs.org/protobufjs/-/protobufjs-7.5.4.tgz",
-      "integrity": "sha512-CvexbZtbov6jW2eXAvLukXjXUW1TzFaivC46BpWc/3BpcCysb5Vffu+B3XHMm8lVEuy2Mm4XGex8hBSg1yapPg==",
+      "version": "7.5.5",
+      "resolved": "https://registry.npmjs.org/protobufjs/-/protobufjs-7.5.5.tgz",
+      "integrity": "sha512-3wY1AxV+VBNW8Yypfd1yQY9pXnqTAN+KwQxL8iYm3/BjKYMNg4i0owhEe26PWDOMaIrzeeF98Lqd5NGz4omiIg==",
       "hasInstallScript": true,
       "license": "BSD-3-Clause",
       "dependencies": {
@@ -5532,7 +5535,7 @@
     },
     "packages/core": {
       "name": "@paddleocr/paddleocr-js",
-      "version": "0.3.1",
+      "version": "0.3.2",
       "license": "Apache-2.0",
       "dependencies": {
         "@techstark/opencv-js": "^4.10.0-release.1",
diff --git a/paddleocr-js/package.json b/paddleocr-js/package.json
index b35634b5612..d8a79c019ea 100644
--- a/paddleocr-js/package.json
+++ b/paddleocr-js/package.json
@@ -64,5 +64,8 @@
     "*.{json,md,html,css,yaml,yml}": [
       "prettier --write"
     ]
+  },
+  "dependencies": {
+    "protobufjs": "^7.5.5"
   }
 }
diff --git a/tests/test_invariant_package-lock.py b/tests/test_invariant_package-lock.py
new file mode 100644
index 00000000000..70524cb9ace
--- /dev/null
+++ b/tests/test_invariant_package-lock.py
@@ -0,0 +1,182 @@
+import pytest
+import json
+import re
+
+
+ADVERSARIAL_PAYLOADS = [
+    # Prototype pollution via __proto__
+    '{"__proto__": {"polluted": true}}',
+    # Constructor injection
+    '{"constructor": {"prototype": {"polluted": true}}}',
+    # Type field injection (protobufjs specific)
+    '{"type": "constructor"}',
+    '{"type": "__proto__"}',
+    '{"type": "Object"}',
+    # Nested type injection
+    '{"fields": {"x": {"type": "constructor"}}}',
+    '{"fields": {"x": {"type": "__proto__"}}}',
+    # Arbitrary code execution via type fields
+    '{"nested": {"Evil": {"fields": {"x": {"type": "constructor.prototype"}}}}}',
+    # JSON with injected protobuf definition type fields
+    '{"options": {"(evil)": "constructor"}}',
+    # Null byte injection
+    '{"type": "string\x00constructor"}',
+    # Unicode escape injection
+    '{"type": "\\u005f\\u005fproto\\u005f\\u005f"}',
+    # Deep nesting attack
+    '{"a": {"b": {"c": {"d": {"type": "constructor"}}}}}',
+    # Array with malicious type
+    '{"fields": [{"type": "constructor"}, {"type": "__proto__"}]}',
+    # Mixed case bypass attempts
+    '{"type": "Constructor"}',
+    '{"type": "__PROTO__"}',
+    '{"type": "CONSTRUCTOR"}',
+    # Whitespace bypass
+    '{"type": " constructor "}',
+    '{"type": "\tconstructor\t"}',
+    # Dot notation injection
+    '{"type": "Object.prototype"}',
+    '{"type": "Function.prototype"}',
+    # Eval-like strings
+    '{"type": "eval"}',
+    '{"type": "Function"}',
+    # Empty and boundary values
+    '{"type": ""}',
+    '{"type": null}',
+    '{"type": 0}',
+    '{"type": []}',
+    # Deeply nested prototype pollution
+    '{"a": {"__proto__": {"polluted": "yes"}}}',
+    # toString/valueOf override attempts
+    '{"toString": "constructor"}',
+    '{"valueOf": "__proto__"}',
+]
+
+
+def is_safe_protobuf_type(type_value: str) -> bool:
+    """
+    Check if a protobuf type field value is safe.
+    Safe types are standard protobuf scalar types or valid message names
+    that don't reference dangerous JavaScript properties.
+    """
+    DANGEROUS_IDENTIFIERS = {
+        '__proto__', 'constructor', 'prototype', 'eval',
+        'function', 'object', 'Function', 'Object',
+        '__defineGetter__', '__defineSetter__', '__lookupGetter__',
+        '__lookupSetter__', 'hasOwnProperty', 'isPrototypeOf',
+        'propertyIsEnumerable', 'toString', 'valueOf',
+    }
+
+    VALID_PROTOBUF_SCALAR_TYPES = {
+        'double', 'float', 'int32', 'int64', 'uint32', 'uint64',
+        'sint32', 'sint64', 'fixed32', 'fixed64', 'sfixed32', 'sfixed64',
+        'bool', 'string', 'bytes',
+    }
+
+    if not isinstance(type_value, str):
+        return True  # Non-string types are handled separately
+
+    stripped = type_value.strip()
+
+    # Check against dangerous identifiers (case-insensitive)
+    if stripped.lower() in {d.lower() for d in DANGEROUS_IDENTIFIERS}:
+        return False
+
+    # Check for prototype chain access patterns
+    if re.search(r'(prototype|__proto__|constructor)', stripped, re.IGNORECASE):
+        return False
+
+    # Check for dot notation that could access dangerous properties
+    if '.' in stripped:
+        parts = stripped.split('.')
+        for part in parts:
+            if part.lower() in {d.lower() for d in DANGEROUS_IDENTIFIERS}:
+                return False
+
+    return True
+
+
+def extract_type_fields(obj, path=""):
+    """Recursively extract all 'type' field values from a parsed JSON object."""
+    type_fields = []
+    if isinstance(obj, dict):
+        for key, value in obj.items():
+            current_path = f"{path}.{key}" if path else key
+            if key == 'type' and isinstance(value, str):
+                type_fields.append((current_path, value))
+            elif isinstance(value, (dict, list)):
+                type_fields.extend(extract_type_fields(value, current_path))
+    elif isinstance(obj, list):
+        for i, item in enumerate(obj):
+            type_fields.extend(extract_type_fields(item, f"{path}[{i}]"))
+    return type_fields
+
+
+def check_prototype_pollution(obj, path=""):
+    """Check if parsed JSON object contains prototype pollution keys."""
+    DANGEROUS_KEYS = {'__proto__', 'constructor', 'prototype'}
+    violations = []
+    if isinstance(obj, dict):
+        for key, value in obj.items():
+            current_path = f"{path}.{key}" if path else key
+            if key in DANGEROUS_KEYS:
+                violations.append((current_path, key))
+            if isinstance(value, (dict, list)):
+                violations.extend(check_prototype_pollution(value, current_path))
+    elif isinstance(obj, list):
+        for i, item in enumerate(obj):
+            violations.extend(check_prototype_pollution(item, f"{path}[{i}]"))
+    return violations
+
+
+@pytest.mark.parametrize("payload", ADVERSARIAL_PAYLOADS)
+def test_protobuf_type_field_injection_safety(payload):
+    """
+    Invariant: Protobuf definition type fields must never reference dangerous
+    JavaScript properties (constructor, __proto__, prototype, eval, etc.)
+    that could lead to arbitrary code execution or prototype pollution.
+    Any parsed protobuf definition must have safe type field values and
+    must not contain prototype pollution keys.
+    """
+    # Attempt to parse the payload as JSON (simulating protobuf definition parsing)
+    try:
+        parsed = json.loads(payload)
+    except (json.JSONDecodeError, ValueError):
+        # If payload is not valid JSON, it cannot be a valid protobuf definition
+        # This is safe - invalid input is rejected
+        return
+
+    # INVARIANT 1: No prototype pollution keys should be present at any level
+    pollution_violations = check_prototype_pollution(parsed)
+    assert len(pollution_violations) == 0, (
+        f"Prototype pollution keys found in payload: {pollution_violations}. "
+        f"Payload: {payload}"
+    )
+
+    # INVARIANT 2: All 'type' fields must be safe (no dangerous identifiers)
+    type_fields = extract_type_fields(parsed)
+    for field_path, type_value in type_fields:
+        assert is_safe_protobuf_type(type_value), (
+            f"Dangerous type field value '{type_value}' found at path '{field_path}'. "
+            f"This could lead to arbitrary code execution via injected protobuf "
+            f"definition type fields. Payload: {payload}"
+        )
+
+    # INVARIANT 3: Type fields must not contain null bytes
+    for field_path, type_value in type_fields:
+        assert '\x00' not in type_value, (
+            f"Null byte found in type field at path '{field_path}': {repr(type_value)}. "
+            f"Payload: {payload}"
+        )
+
+    # INVARIANT 4: Type fields must not contain prototype chain access patterns
+    PROTOTYPE_CHAIN_PATTERN = re.compile(
+        r'(prototype|__proto__|constructor)',
+        re.IGNORECASE
+    )
+    for field_path, type_value in type_fields:
+        assert not PROTOTYPE_CHAIN_PATTERN.search(type_value), (
+            f"Prototype chain access pattern found in type field at path "
+            f"'{field_path}': '{type_value}'. "
+            f"This violates the security boundary. Payload: {payload}"
+        )
\ No newline at end of file