diff --git a/cms/djangoapps/contentstore/tests/test_course_listing.py b/cms/djangoapps/contentstore/tests/test_course_listing.py
index 8d3bd47f79c4..fb4e66c8c5c2 100644
--- a/cms/djangoapps/contentstore/tests/test_course_listing.py
+++ b/cms/djangoapps/contentstore/tests/test_course_listing.py
@@ -936,7 +936,9 @@ def test_get_course_keys_from_scopes_with_platform_scope(self):
             "is_enabled",
             side_effect=self._mock_authz_toggle(enabled_keys),
         ):
-            course_keys = _get_course_keys_from_scopes([PlatformCourseOverviewGlobData(external_key="course-v1:*")])
+            course_keys = _get_course_keys_from_scopes([
+                PlatformCourseOverviewGlobData(external_key=PlatformCourseOverviewGlobData.build_external_key())
+            ])
 
         assert course_keys == set(authz_keys) | set(legacy_keys)
 
@@ -953,7 +955,9 @@ def test_get_course_keys_from_scopes_with_platform_scope_global_flag_enabled(sel
             "is_enabled",
             side_effect=self._mock_authz_toggle(enabled_keys, global_enabled=True),
         ):
-            course_keys = _get_course_keys_from_scopes([PlatformCourseOverviewGlobData(external_key="course-v1:*")])
+            course_keys = _get_course_keys_from_scopes([
+                PlatformCourseOverviewGlobData(external_key=PlatformCourseOverviewGlobData.build_external_key())
+            ])
 
         assert course_keys == set(CourseOverview.get_all_courses().values_list("id", flat=True))
 
@@ -972,8 +976,8 @@ def test_get_course_keys_from_scopes_platform_scope_short_circuits(self):
         ):
             course_keys = _get_course_keys_from_scopes(
                 [
-                    OrgCourseOverviewGlobData(external_key="course-v1:Org1+*"),
-                    PlatformCourseOverviewGlobData(external_key="course-v1:*"),
+                    OrgCourseOverviewGlobData(external_key=OrgCourseOverviewGlobData.build_external_key("Org1")),
+                    PlatformCourseOverviewGlobData(external_key=PlatformCourseOverviewGlobData.build_external_key()),
                 ]
             )
 
diff --git a/common/djangoapps/student/roles.py b/common/djangoapps/student/roles.py
index 81a28773950f..58e91bf96b68 100644
--- a/common/djangoapps/student/roles.py
+++ b/common/djangoapps/student/roles.py
@@ -17,6 +17,7 @@
 from openedx_authz.api import users as authz_api
 from openedx_authz.api.data import CourseOverviewData, OrgCourseOverviewGlobData, RoleAssignmentData
 from openedx_authz.constants import roles as authz_roles
+from organizations.api import get_organizations
 
 from common.djangoapps.student.models import CourseAccessRole
 from common.djangoapps.student.signals.signals import emit_course_access_role_added, emit_course_access_role_removed
@@ -632,6 +633,11 @@ def _authz_get_orgs_for_user(self, user) -> list[str]:
             user_external_key=user.username,
             role_external_key=role,
         )
+        # A platform-wide grant (course-v1:*, lib:*) covers every org, not just the ones
+        # with a concrete assignment. Platform-glob scopes have no .org attribute at all
+        # (unlike org-glob/course/library scopes, where it's a real field that can be None).
+        if any(assignment.scope.IS_PLATFORM_GLOB for assignment in assignments):
+            return [org["short_name"] for org in get_organizations()]
         orgs = {assignment.scope.org for assignment in assignments if assignment.scope.org is not None}
         return list(orgs)
 
diff --git a/common/djangoapps/student/tests/test_roles.py b/common/djangoapps/student/tests/test_roles.py
index 1979bc6687fd..07326fd85ebf 100644
--- a/common/djangoapps/student/tests/test_roles.py
+++ b/common/djangoapps/student/tests/test_roles.py
@@ -14,6 +14,7 @@
     ContentLibraryData,
     CourseOverviewData,
     OrgCourseOverviewGlobData,
+    PlatformCourseOverviewGlobData,
     RoleAssignmentData,
     RoleData,
     ScopeData,
@@ -21,6 +22,7 @@
 )
 from openedx_authz.constants.roles import COURSE_ADMIN, COURSE_STAFF
 from openedx_authz.engine.enforcer import AuthzEnforcer
+from organizations.api import add_organization
 
 from common.djangoapps.student.admin import CourseAccessRoleHistoryAdmin
 from common.djangoapps.student.models import CourseAccessRoleHistory, User
@@ -313,6 +315,33 @@ def test_get_orgs_for_user_authz(self):
             result = role.get_orgs_for_user(self.student)
             self.assertCountEqual(result, [self.course_key.org, other_org])  # noqa: PT009
 
+    @override_waffle_flag(AUTHZ_COURSE_AUTHORING_FLAG, active=True)
+    def test_get_orgs_for_user_authz_platform_glob(self):
+        """
+        A platform-wide glob assignment (course-v1:*) has no `.org` attribute, unlike
+        course/org-glob scopes. get_orgs_for_user must special-case it and return every
+        registered org instead of crashing with an AttributeError.
+        """
+        role = CourseStaffRole(self.course_key)
+
+        for org in self.orgs:
+            add_organization({"name": org, "short_name": org, "description": ""})
+
+        staff_authz_role = RoleData(external_key=COURSE_STAFF)
+        assignments = [
+            RoleAssignmentData(
+                subject=UserData(external_key=self.student.username),
+                roles=[staff_authz_role],
+                scope=PlatformCourseOverviewGlobData(external_key=PlatformCourseOverviewGlobData.build_external_key()),
+            ),
+        ]
+
+        with patch("openedx_authz.api.users.get_user_role_assignments_filtered", return_value=assignments):
+            result = role.get_orgs_for_user(self.student)
+            self.assertCountEqual(result, self.orgs)  # noqa: PT009
+            assert role.has_org_for_user(self.student)
+            assert role.has_org_for_user(self.student, org=self.orgs[0])
+
     def test_get_authz_compat_course_access_roles_for_user(self):
         """
         Test that get_authz_compat_course_access_roles_for_user doesn't crash when the user