Worked on the TencentBlueKing/bk-lite repository to deliver a targeted security enhancement for QCloud credential management. Addressed a critical bug by correcting a typo in the encrypted fields, ensuring that sensitive credentials are now properly encrypted at rest and consistently masked in API responses. The solution involved cross-component debugging and updates to Python data models, runtime decryption logic, and serializer representations, preventing plaintext storage and accidental exposure during UI edits or GET requests. Leveraged backend development skills with a focus on data security and encryption, aligning QCloud credential handling with existing naming conventions to improve overall security and data governance.