What AppSec Engineers Actually Do (and Why It Matters)

Imagine a team building a simple feature: an endpoint to let users download their invoices. The implementation is straightforward: check the user is authenticated, fetch the file, and return it. It passes code review, tests are green, and it ships. A few weeks later, someone realizes you can tweak a parameter and download another user’s invoice, and the team now has to rush to fix this security issue. No software engineer sets out to write insecure code. However, stories like this one keep happe