Secure coding skills
for developer jobs in 2027

Attackers increasingly get in through software flaws. Verizon's 2026 Data Breach Investigations Report, as reported by Infosecurity Magazine, found exploitation of vulnerabilities was the initial access vector in 31% of breaches — up from 20% the year before and now the top route in — while third-party and supply-chain involvement appeared in 48% of breaches.¹ Governments are pushing the same direction: CISA's Secure by Design initiative asks software makers to take ownership of customer security outcomes,⁶ and NIST's Secure Software Development Framework lists practices developers are expected to follow.⁵

For job seekers, that means secure coding questions now appear in ordinary developer interviews, not just security roles. Software engineers in India typically earned ₹9.3–10.2 lakh on AmbitionBox in October 2026,⁷ and developers who add application security skills open DevSecOps and AppSec paths.

Breaches starting with vulnerability exploitation (Verizon DBIR 2026)

31%

Breaches involving third parties or the supply chain (DBIR 2026)

48%

Broken access control's rank in the OWASP Top 10

#1

Often all it takes to fix — or create — an access-control bug

1 line

Table: How secure coding is tested (editorial summary)

The OWASP Top 10,² its Cheat Sheet Series⁴ and the Application Security Verification Standard (ASVS)³ are the most practical free references.

# Vulnerable: SQL injection and missing ownership check
@app.get("/statements/<sid>")
def get_statement(sid):
    row = db.execute(f"SELECT * FROM statements WHERE id = {sid}").fetchone()
    return jsonify(row)

# Fixed: parameterised query + authorisation on the object
@app.get("/statements/<int:sid>")
@login_required
def get_statement(sid):
    row = db.execute(
        "SELECT * FROM statements WHERE id = ? AND user_id = ?",
        (sid, current_user.id),
    ).fetchone()
    if row is None:
        abort(404)            # don't reveal whether the statement exists
    return jsonify(row)

What to say: the query no longer concatenates input, so injection is prevented; the ownership condition enforces access control on the specific object; the 404 avoids revealing other users' resources; and the route type check rejects non-numeric IDs early.

"How should passwords be stored?"

With a slow, salted password-hashing algorithm such as Argon2, bcrypt or scrypt — never plain text or fast hashes like plain SHA-256.

"What is CSRF and how do you prevent it?"

A malicious site makes a logged-in user's browser send a request; prevent with anti-CSRF tokens, SameSite cookies and checking origins for state-changing requests.

"How do you handle secrets?"

Store them in a secrets manager or environment-specific store, never in code or logs; rotate them; restrict access.

"A dependency has a critical vulnerability. What do you do?"

Check whether you use the affected code, upgrade or patch quickly, add a temporary mitigation if needed, and improve automated scanning.

"How do you secure file uploads?"

Validate type and size, store outside the web root or in object storage, generate new filenames, scan where needed and serve with safe content types.

"What is insecure deserialisation?"

Deserialising untrusted data into objects can trigger code execution; avoid native serialisation of untrusted input and use safe formats like JSON with schemas.

"Why is client-side validation not enough?"

Attackers bypass the client; the server must validate and authorise everything.

"What does 'secure by default' mean?"

Safe settings out of the box — escaping on, least privilege, secure cookies — so developers must opt out of safety, not opt in.

Table: How secure coding expectations have changed (editorial summary)

1. Break a training app — Use an intentionally vulnerable app (such as OWASP Juice Shop) to find and fix flaws.
2. One fix per Top 10 item — Write a vulnerable and fixed snippet in your language for each.
3. Scan your project — Run dependency and secret scanning; fix what it finds.
4. Threat-model a feature — List what could go wrong with a file upload or password reset.
5. Review AI code — Ask an assistant for a login endpoint and audit it.

Table: Roles where secure coding matters and typical pay in India (AmbitionBox, October 2026; indicative)

Application security and DevSecOps roles build directly on these skills — see our application security guide.

1. Week 1: OWASP Top 10 — Read each risk with examples in your language.
2. Week 2: Hands-on — Find and fix flaws in a deliberately vulnerable app.
3. Week 3: Your own code — Add scanning, secrets management and access-control tests to a project.
4. Week 4: Prove it — Take the Secure Coding Fundamentals Certification.

Related: Application Security, Threat Modeling and Code Review.

• Every pull request — checking authorisation, validation and error handling in your own and others' changes.
• Dependency updates — triaging scanner alerts and upgrading vulnerable packages.
• Secrets handling — using the team's secrets manager and rotating keys when needed.
• Threat discussions — asking "what could go wrong?" for new features like uploads and payments.
• Security fixes — responding to findings from penetration tests or bug-bounty reports.
• Logging — making sure suspicious activity is visible without logging sensitive data.

"What is SSRF?"

Server-side request forgery: tricking a server into making requests to internal systems. Prevent with allow-lists for destinations, blocking internal address ranges and not fetching arbitrary user-supplied URLs.

"How do you prevent IDOR?"

Insecure direct object references are prevented by checking that the requesting user is allowed to access each specific object, every time — not by hiding IDs.

"What security headers matter for web apps?"

Content-Security-Policy, Strict-Transport-Security, X-Content-Type-Options and appropriate frame and referrer policies.

• Authentication without authorisation.
• String-built queries.
• Secrets in repositories.
• Ignoring dependency alerts.
• Trusting client-side checks.

Breach data comes from Verizon's 2026 DBIR as reported by Infosecurity Magazine. Practice references are OWASP's Top 10, ASVS and Cheat Sheet Series, NIST SP 800-218 (SSDF) and CISA's Secure by Design; pay from AmbitionBox (read October 2026). Test formats and the history table are editorial summaries. Science of Apps publishes the free certification linked here. Last reviewed October 2026.

• Broken access control — users can act on data or functions they shouldn't.
• Injection — untrusted input interpreted as code or commands.
• XSS — cross-site scripting: injecting script into pages other users view.
• CSRF — cross-site request forgery: tricking a browser into sending unwanted requests.
• Software supply chain — the dependencies, tools and pipelines used to build software.
• SSDF — NIST's Secure Software Development Framework.