web
7 articles with this tag
What is CORS — how it works, and what a misconfiguration exposes
CORS is how the browser controls whether another origin's JS can read your API responses. A misconfiguration — reflecting any Origin, or Access-Control-Allow-Origin:* with credentials — lets a third-party site read logged-in data. The basic defense: an allowlist, don't blindly reflect Origin, default deny.
What is session fixation — making a victim log in with an ID the attacker already knows
Session fixation makes a victim use an attacker-known session ID, then impersonates them after they log in with it. The main defense: regenerate the session ID on login (and on privilege change). Don't accept IDs from the URL, and set HttpOnly/Secure/SameSite on cookies.
What is clickjacking? An attack that makes you click buttons on a transparent page laid over another
Clickjacking layers your real site invisibly over an attacker's page so the user performs an unintended action (transfer, settings change, consent). The main defense is refusing to be framed: CSP frame-ancestors plus X-Frame-Options.
What is open redirect: a flaw that forwards users from your trusted URL to another site
An open redirect lets a ?next= style parameter forward users to any external site, borrowing your trusted domain for phishing. The main defense: never accept external URLs as redirect targets; use relative paths and an allowlist only.
What is path traversal — reading files the server should never serve, via ../
Path traversal mixes ../ into a filename input to escape the base directory and read/write .env, config, or keys. The main defense: never use user input as a raw file path, and normalize-then-confine inside an allowed base directory.
What is CSRF (Cross-Site Request Forgery): an attack that makes a logged-in user send requests they did not intend
CSRF makes a logged-in user's browser send an unintended action, abusing the browser's habit of auto-attaching cookies. The main defense is CSRF tokens plus SameSite cookies. Never use GET for state changes.
What is XSS (Cross-Site Scripting): a flaw that runs an attacker's script in another user's browser
XSS makes an attacker-supplied string run 'as script' in another user's browser, leading directly to session theft and impersonation. The main defense is escaping on output. Don't disable your framework's auto-escaping.