FREE SCAN — 150 founder credits, no card

Free Security Scan for Flask Apps

Scan your Flask app for debug-mode RCE, SSTI, and weak sessions.

Why Flask Apps Get Hacked

Flask is minimal by design, so security is on you. The most notorious Flask bug is running with the debugger enabled in production — the Werkzeug debug console allows arbitrary code execution. Add Jinja2 server-side template injection and weak SECRET_KEY session signing, and a small Flask app can become a full server takeover. We scan for these.

Common Flask Vulnerabilities

Debug mode = remote code execution

Flask's debug=True enables the Werkzeug interactive debugger. If reachable in production, it allows arbitrary Python execution — instant full compromise.

Jinja2 SSTI

Rendering user input through render_template_string or untrusted templates leads to server-side template injection, often escalating to RCE.

Weak SECRET_KEY / session forgery

Flask sessions are client-side signed cookies. A weak, default, or leaked SECRET_KEY lets attackers forge any session, including admin.

Missing security headers & CSRF

Flask adds no security headers and no CSRF protection out of the box; both must be added (Talisman, Flask-WTF) and usually are not.

Verbose errors

Unhandled exceptions leak stack traces and internal paths that help an attacker map and target the app.

What the Sable Scan Checks

Exposed secrets & API keys

We scan your client-side bundles and responses for leaked API keys, tokens, database URLs, and 100+ secret patterns that ship to the browser by accident.

Security headers & TLS

HSTS, CSP, X-Frame-Options, Referrer-Policy, Permissions-Policy, and TLS protocol/cipher configuration — graded A-F with copy-paste fixes.

CORS & access control

Overly permissive CORS, wildcard origins with credentials, and broken object-level authorization (IDOR/BOLA) where one user can reach another user's data.

Injection & API surface

SQL/NoSQL injection, exposed OpenAPI/Swagger specs, GraphQL introspection, mass assignment, missing rate limits, and excessive data exposure.

OWASP Top 10 coverage

Autonomous pentesting agents test against the full OWASP Top 10 2025, validate each finding with a proof-of-concept, and re-test after you fix.

Validated findings, not noise

Every reported issue is confirmed by an agent before it reaches you — so you get real, exploitable findings with severity and remediation, not scanner spam.

Scan Your Flask App in Minutes

Create a free account, point the agents at your app, and get validated findings with proof-of-concept and fix guidance. 150 founder credits, no credit card.

Get 150 Free Credits

Frequently Asked Questions

Why is Flask debug mode a critical risk?
With debug=True, Flask exposes the Werkzeug debugger, whose console can execute arbitrary Python on your server. If that page is reachable in production it is a direct path to full compromise. Always run with debug off in production. Sable detects exposed debug consoles.
How serious is a weak Flask SECRET_KEY?
Very. Flask signs session cookies with SECRET_KEY, so a weak or leaked key lets an attacker forge any session — including an admin session. Use a long random key, keep it server-only, and rotate if exposed. Sable flags session and secret-handling weaknesses.
Is the security scan really free?
Yes. The Headers Scan runs instantly with no signup. For the full agent scan you create a free account and get 150 founder credits with no credit card required — enough to run real scans against your app on demand. Paid credit packs and monthly tiers exist for continuous testing, but you can start for free.
How does Sable scan my app?
Sable runs autonomous pentesting agents (pen-scout, pen-recon, pen-triage, pen-fixer, pen-compliance) that map your attack surface, test against the OWASP Top 10, validate every finding with a proof-of-concept, and re-test after you ship a fix. You chat with the agents on demand instead of waiting weeks for a manual engagement.
Will the scan break or slow down my production app?
No. Scans are designed to be safe and non-destructive. We demonstrate impact with proof-of-concept evidence rather than causing damage, and we never exfiltrate or alter your data.

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