diff --git a/changes/10342.fix.md b/changes/10342.fix.md
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+++ b/changes/10342.fix.md
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+Add migration to convert deprecated global-scoped permissions to domain-scoped equivalents, fixing `RBACTypeConversionError` in `adminPermissions` GraphQL query.
diff --git a/src/ai/backend/manager/models/alembic/versions/5a4e677aea42_convert_global_permissions_to_domain.py b/src/ai/backend/manager/models/alembic/versions/5a4e677aea42_convert_global_permissions_to_domain.py
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+++ b/src/ai/backend/manager/models/alembic/versions/5a4e677aea42_convert_global_permissions_to_domain.py
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+"""convert global-scoped permissions to domain-scoped
+
+Revision ID: 5a4e677aea42
+Revises: 0e0723286a7a
+Create Date: 2026-03-20 00:00:00.000000
+
+"""
+
+import sqlalchemy as sa
+from alembic import op
+
+# revision identifiers, used by Alembic.
+revision = "5a4e677aea42"
+down_revision = "0e0723286a7a"
+branch_labels = None
+depends_on = None
+
+
+def upgrade() -> None:
+    conn = op.get_bind()
+
+    # Convert global-scoped permissions to domain-scoped by creating one row
+    # per active domain for each global permission row.
+    # ON CONFLICT DO NOTHING handles the unique constraint
+    # (role_id, scope_type, scope_id, entity_type, operation).
+    conn.execute(
+        sa.text(
+            "INSERT INTO permissions (id, role_id, scope_type, scope_id, entity_type, operation)"
+            " SELECT uuid_generate_v4(), p.role_id, 'domain', d.name, p.entity_type, p.operation"
+            " FROM permissions AS p"
+            " CROSS JOIN domains AS d"
+            " WHERE p.scope_type = 'global' AND d.is_active IS TRUE"
+            " ON CONFLICT ON CONSTRAINT uq_permissions_role_scope_entity_op DO NOTHING"
+        )
+    )
+
+    # Delete all global-scoped permission rows now that they are converted
+    conn.execute(sa.text("DELETE FROM permissions WHERE scope_type = 'global'"))
+
+
+def downgrade() -> None:
+    # Global scope is deprecated and has no corresponding RBACElementType.
+    # The conversion to domain-scoped permissions is not reversible because
+    # we cannot determine which domain-scoped rows were originally global.
+    pass