Upon leaving a job, return all account access rights; do not delete databases, leave backdoors, or alter password protection systems — even if the employer owes you wages.

No cost involved. If the employer owes you wages, pursue them through labor arbitration (see Section 7 on labor arbitration). The real challenge is resisting the urge to tamper with the system while angry.

Illegal control of computer information systems is punishable by up to 3 years in prison, with or without a fine; more serious cases incur sentences ranging from 3 to 7 years. Deleting or altering system functions or data to the point the system cannot operate normally is punishable by up to 5 years in prison; more severe cases incur sentences exceeding 5 years. Official cases include: after being dismissed, senior IT engineer Lü used his original admin account to access his former employer’s shared servers, changed passwords, and deleted data and logs, causing over 120,000 yuan in losses; he received the same sentence as above. Another case: Bai, an employee at a software firm, deliberately inserted faulty code into an upgrade program, rendering client systems inaccessible and causing over 40,000 yuan in losses; he was prosecuted for disrupting computer information systems nationwide.

全国人大 (2020). 刑法（根据刑法修正案（十一）修正，第二百八十五条第二款、第二百八十六条）. https://jtgl.beijing.gov.cn/jgj/jgxx/flfg/fl/11033925/index.html；最高人民检察院 (2024). 检察机关「依法惩治网络犯罪 助力网络空间综合治理」典型案例（案例六）. https://www.spp.gov.cn/xwfbh/wsfbh/202402/t20240223_644505.shtml；最高人民检察院 (2025). 检察机关依法惩治侵害企业数据安全犯罪 服务保障企业创新发展（案例七）. https://www.spp.gov.cn/xwfbh/wsfbh/202501/t20250124_680670.shtml

Account credentials are issued by the employer, but they do not remain valid after you leave the job. Logging in using original credentials constitutes “illegal control.” Losses are calculated based on data recovery costs; amounts in the tens of thousands of yuan are sufficient to initiate legal proceedings.