Secure SDLC. Security built in, not bolted on.
About something that at many firms is stuck in the past: security tacked on at the end, right before the release. A Secure SDLC does the opposite; which is exactly why it works.
You know the pattern: feature is done, deadline is tomorrow, and someone asks “did we do security?” Then the theatre begins. A Secure Software Development Lifecycle (Secure SDLC) structures things so security is present at every stage; not as a last-minute panic patch.
TL;DR
- Security built into every stage: requirements, design, code, testing, release, maintenance
- Fixing a vulnerability in the design phase is cheap; fixing it in production is expensive
- Pillars: threat modeling, secure coding, code review, testing (SAST/DAST/dependencies), vulnerability management
- Also a requirement of mature regulations: NIS2 Art. 21 explicitly mentions secure development
Why “at the end” does not work
The later you catch a vulnerability, the more it costs. A bug in requirements costs a conversation. The same bug in production costs an incident, a hotfix patch, and sometimes a regulatory notification. Secure SDLC shifts detection left, to the stages where a fix is cheap.
The stages, in brief
Requirements: you add security and privacy requirements alongside functional ones. Design: threat modeling; asking “how can this be broken” before anything is built. Code: secure coding plus mandatory code review. Testing: SAST, DAST, dependency scanning, security tests. Release: quality gates, signing, pipeline access control. Maintenance: vulnerability management and incident response.
Secure SDLC and regulations
This is not just engineering hygiene. NIS2 Art. 21 lists security in the acquisition, development, and maintenance of systems. DORA expects control over ICT risk, including risk introduced by your own software. ISO 27001 has dedicated controls for the development lifecycle. If you build software and fall under any of these regulations, Secure SDLC does double duty: it protects the product and satisfies a requirement.
How to tie it together
The key point: secure development does not live alongside the rest of compliance; it is part of it. An SDLC policy, threat modeling, and vulnerability management are elements of the same system that also holds risk, controls, and evidence.
In RealSec we connect all of this: the CISO module holds the ISMS and controls, the ISO 27001 module maps development lifecycle controls, and the Risk Engine calculates the risk that software introduces. The secure development policy itself; ready-made for a software-producing company; is included in the security documentation package. No theatre, with evidence.
Written by someone on the RealSec team. Want to talk specifics ; get in touch.