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.
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