assertEquals("S-1-5-10-20", sid.toString());
        }

        @Test
        @DisplayName("Binary constructor with invalid sub_authority_count throws RuntimeCIFSException")
        void testBinaryConstructorInvalidCount() {
            // Arrange: second byte is sub_authority_count > 100
            byte[] bytes = new byte[1 + 1 + 6];
            bytes[0] = 1; // revision
            bytes[1] = (byte) 101; // invalid count