1e41f4b71Sopenharmony_ci# Common Capability Changelog 2e41f4b71Sopenharmony_ci 3e41f4b71Sopenharmony_ci## cl.common.1 System API Usage Rule Changed 4e41f4b71Sopenharmony_ci 5e41f4b71Sopenharmony_ciWhen a system API is called, no verification is performed to check whether the caller is a system application or third-party application. As a result, a third-party application can switch to the full SDK to use system APIs, which brings security risks. To address this issue, application identity verification is added to OpenHarmony 4.0.2.1 and later versions. 6e41f4b71Sopenharmony_ci 7e41f4b71Sopenharmony_ci**Change Impact** 8e41f4b71Sopenharmony_ci 9e41f4b71Sopenharmony_ciSystem APIs are available only to system applications. When a third-party application tries to use a system API, the **202** error will be returned via either an exception or asynchronous callback. 10e41f4b71Sopenharmony_ci 11e41f4b71Sopenharmony_ci**Adaptation Guide** 12e41f4b71Sopenharmony_ci 13e41f4b71Sopenharmony_ciTo use a system API, a third-party application must either request the system application permission or use a substitute API that is available for non-system applications. 14