diff --git a/src/debugpy/_vendored/__init__.py b/src/debugpy/_vendored/__init__.py
index 0d6376ae6..abde2e333 100644
--- a/src/debugpy/_vendored/__init__.py
+++ b/src/debugpy/_vendored/__init__.py
@@ -15,16 +15,14 @@
 VENDORED_ROOT = os.path.dirname(os.path.abspath(__file__))
 # TODO: Move the "pydevd" git submodule to the debugpy/_vendored directory
 # and then drop the following fallback.
-if 'pydevd' not in os.listdir(VENDORED_ROOT):
+if "pydevd" not in os.listdir(VENDORED_ROOT):
     VENDORED_ROOT = os.path.dirname(VENDORED_ROOT)
 
 
 def list_all(resolve=False):
     """Return the list of vendored projects."""
     # TODO: Derive from os.listdir(VENDORED_ROOT)?
-    projects = [
-        'pydevd',
-    ]
+    projects = ["pydevd"]
     if not resolve:
         return projects
     return [project_root(name) for name in projects]
@@ -37,7 +35,7 @@ def project_root(project):
     projects (e.g. "debugpy/_vendored/") will be returned.
     """
     if not project:
-        project = ''
+        project = ""
     return os.path.join(VENDORED_ROOT, project)
 
 
@@ -63,17 +61,14 @@ def iter_packaging_files(project):
     prune_dir = None
     exclude_file = None
     try:
-        mod = import_module('._{}_packaging'.format(project), __name__)
+        mod = import_module("._{}_packaging".format(project), __name__)
     except ImportError:
         pass
     else:
-        prune_dir = getattr(mod, 'prune_dir', prune_dir)
-        exclude_file = getattr(mod, 'exclude_file', exclude_file)
+        prune_dir = getattr(mod, "prune_dir", prune_dir)
+        exclude_file = getattr(mod, "exclude_file", exclude_file)
     results = iter_project_files(
-        project,
-        relative=True,
-        prune_dir=prune_dir,
-        exclude_file=exclude_file,
+        project, relative=True, prune_dir=prune_dir, exclude_file=exclude_file
     )
     for _, _, filename in results:
         yield filename
@@ -89,6 +84,7 @@ def match(name, module):
                 return True
         else:
             return False
+
     return match
 
 
@@ -101,10 +97,14 @@ def check_modules(project, match, root=None):
     for modname, mod in list(sys.modules.items()):
         if not match(modname, mod):
             continue
-        if not hasattr(mod, '__file__'):  # extension module
+        try:
+            filename = getattr(mod, "__file__", None)
+        except:  # In theory it's possible that any error is raised when accessing __file__
+            filename = None
+        if not filename:  # extension module
             extensions.append(modname)
-        elif not mod.__file__.startswith(root):
-            unvendored[modname] = mod.__file__
+        elif not filename.startswith(root):
+            unvendored[modname] = filename
     return unvendored, extensions
 
 
diff --git a/src/debugpy/_vendored/pydevd/_pydev_bundle/_pydev_imports_tipper.py b/src/debugpy/_vendored/pydevd/_pydev_bundle/_pydev_imports_tipper.py
index 510fc820d..7ba858d98 100644
--- a/src/debugpy/_vendored/pydevd/_pydev_bundle/_pydev_imports_tipper.py
+++ b/src/debugpy/_vendored/pydevd/_pydev_bundle/_pydev_imports_tipper.py
@@ -86,12 +86,14 @@ def get_file(mod):
     try:
         f = inspect.getsourcefile(mod) or inspect.getfile(mod)
     except:
-        if hasattr_checked(mod, '__file__'):
-            f = mod.__file__
-            if f.lower(f[-4:]) in ['.pyc', '.pyo']:
-                filename = f[:-4] + '.py'
-                if os.path.exists(filename):
-                    f = filename
+        try:
+            f = getattr(mod, '__file__', None)
+        except:
+            f = None
+        if f and f.lower(f[-4:]) in ['.pyc', '.pyo']:
+            filename = f[:-4] + '.py'
+            if os.path.exists(filename):
+                f = filename
 
     return f
 
diff --git a/src/debugpy/_vendored/pydevd/_pydev_bundle/_pydev_jy_imports_tipper.py b/src/debugpy/_vendored/pydevd/_pydev_bundle/_pydev_jy_imports_tipper.py
index 28d5f6b19..558d5632e 100644
--- a/src/debugpy/_vendored/pydevd/_pydev_bundle/_pydev_jy_imports_tipper.py
+++ b/src/debugpy/_vendored/pydevd/_pydev_bundle/_pydev_jy_imports_tipper.py
@@ -56,8 +56,10 @@ def Find(name):
     parent = mod
     foundAs = ''
 
-    if hasattr(mod, '__file__'):
-        f = mod.__file__
+    try:
+        f = getattr(mod, '__file__', None)
+    except:
+        f = None
 
 
     components = name.split('.')
diff --git a/src/debugpy/_vendored/pydevd/stubs/_get_tips.py b/src/debugpy/_vendored/pydevd/stubs/_get_tips.py
index b98e1c536..79dffaaa0 100644
--- a/src/debugpy/_vendored/pydevd/stubs/_get_tips.py
+++ b/src/debugpy/_vendored/pydevd/stubs/_get_tips.py
@@ -62,9 +62,12 @@ def GetFile(mod):
     try:
         f = inspect.getsourcefile(mod) or inspect.getfile(mod)
     except:
-        if hasattr(mod, '__file__'):
-            f = mod.__file__
-            if f.lower(f[-4:]) in ['.pyc', '.pyo']:
+        try:
+            f = getattr(mod, '__file__', None)
+        except:
+            pass
+        else:
+            if f and f.lower(f[-4:]) in ['.pyc', '.pyo']:
                 filename = f[:-4] + '.py'
                 if os.path.exists(filename):
                     f = filename
diff --git a/tests/tests/test_vendoring.py b/tests/tests/test_vendoring.py
new file mode 100644
index 000000000..dd6c4269b
--- /dev/null
+++ b/tests/tests/test_vendoring.py
@@ -0,0 +1,34 @@
+def test_vendoring(pyfile):
+    @pyfile
+    def import_debugpy():
+        import sys
+
+        class Dummy(object):
+            __file__ = None
+
+        class Dummy2(object):
+            pass
+        
+        class Dummy3(object):
+            def __getattribute__(self, *args, **kwargs):
+                raise AssertionError('Error')
+
+        sys.modules["pydev_dummy"] = Dummy()
+        sys.modules["pydev_dummy2"] = Dummy2()
+        sys.modules["pydev_dummy3"] = Dummy3()
+        
+        sys.modules["_pydev_dummy"] = Dummy()
+        sys.modules["_pydev_dummy2"] = Dummy2()
+        sys.modules["_pydev_dummy3"] = Dummy3()
+
+        from debugpy._vendored import force_pydevd  # noqa
+
+        print("Properly applied pydevd vendoring.")
+
+    import subprocess
+    import sys
+
+    output = subprocess.check_output([sys.executable, "-u", import_debugpy.strpath])
+    output = output.decode("utf-8")
+    if "Properly applied pydevd vendoring." not in output:
+        raise AssertionError(output)