Pro PHP Security: From Application Security Principles to the Implementation of XSS Defenses, Second Edition

Preventing Accidental Corruption

Your first concern, when examining strategies to prevent data loss, is preventing your users from changing or deleting data in the first place, except in those cases where it is absolutely necessary. Your application should prevent the corruption of records that shouldn't be changed, and the destruction of those that shouldn't be deleted, by implementing two subsystems: record locking and delete confirmation.

When a record or file is locked by your application, it cannot be accidentally changed or deleted from within the application's interface. This isn't so much a security feature as it is a hedge against irresponsible or impulsive use, but we mention it here because it can be used to force a separation of privileges: ...