Error map
invalid csrf token ForbiddenError: invalid csrf token (EBADCSRFTOKEN)
Authentication · layer 4, Application & API
Centre: this error. First ring: errors it is linked with (12). Outer ring: what those are linked with. Colours show the layer of a request each error belongs to. Click any dot to re-centre the map on it; hover to follow its connections. The centre dot opens the error page.
Directly related (12)
Cloudflare Error 1015: You are being rate limited
The site’s Cloudflare rate-limiting rule blocked you for sending too many requests in a short time.
Cloudflare Error 1005: Access denied — The owner of this website has banned the autonomous system number (ASN) your IP address is in
The site owner blocked your network provider (ASN) — common for VPNs, cloud/data-center IPs and some mobile carriers.
Cloudflare Error 1006 / 1007 / 1008: Access denied — Your IP address has been banned
The site owner (or a Cloudflare security setting) blocked your IP address.
Cloudflare Error 1010: The owner of this website has banned your access based on your browser's signature
Cloudflare’s bot detection blocked the request because its browser fingerprint looks automated.
Passport.js: Error: Failed to serialize user into session
Passport logged a user in but there’s no serializeUser function (or it didn’t call done), so the session can’t store the user.
HTTP 401 Unauthorized
The request has no valid authentication credentials — you need to log in or send a valid token.
Warning: session_start(): Session cannot be started after headers have already been sent
session_start() ran after output was sent, so PHP can’t set the session cookie.
Warning: session_start(): open(/var/lib/php/sessions/sess_x, O_RDWR) failed: Permission denied
PHP can’t write session files to the configured session.save_path.
Cloudflare "Just a moment..." / "Checking your browser" challenge loop (Verify you are human never finishes)
The Cloudflare challenge keeps reloading — the browser can’t pass it because cookies/JavaScript are blocked, the clock is wrong,…
API/app requests get 403 with cf-mitigated: challenge (Bot Fight Mode / challenge on non-browser clients)
Cloudflare is answering API calls, webhooks or mobile-app requests with a challenge page (HTML 403) because bot protection treats…
InvalidOperationException: Session has not been configured for this application or request
Code used HttpContext.Session, but session services/middleware aren’t registered — or UseSession runs after the endpoint that nee…
WordPress: XML-RPC server accepts POST requests only (xmlrpc.php)
You opened xmlrpc.php in a browser (GET) — it’s an API endpoint, not a page. Heavy POST traffic to it usually means brute-force b…
Two steps away (36)
AWS: ThrottlingException / Rate exceeded
You exceeded the request rate for an AWS API; retry with exponential backoff.
HTTP 429 Too Many Requests
You’ve hit a rate limit — too many requests in a given time window. Slow down and retry later.
Cloudflare Error 1020: Access Denied
A Cloudflare firewall/WAF custom rule blocked the request — the visitor’s IP, country, user agent or request pattern matched a bl…
Webhook signature verification failed (Stripe, Razorpay, GitHub…)
Your endpoint computed a different HMAC signature than the one the provider sent, so the webhook is rejected.
driver failed programming external connectivity on endpoint: iptables: No chain/target/match by that name
Docker’s iptables rules were wiped (firewalld/ufw reload, iptables flush) while Docker was running, so it can’t publish ports.
Error creating: pods is forbidden: violates PodSecurity "restricted:latest": allowPrivilegeEscalation != false ...
The namespace enforces a Pod Security Standard (baseline/restricted) and the pod spec breaks one of its rules.
ssh: connect to host x port 22: Connection timed out
SSH packets get no reply — a firewall/security group drops them, the server is off, or the IP is wrong.
WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! (ssh host key changed)
The server’s SSH host key differs from the one saved in ~/.ssh/known_hosts — usually because the server was rebuilt or the IP was…
The following signatures couldn't be verified because the public key is not available: NO_PUBKEY
apt can’t verify a repository’s signature because the repo’s signing key isn’t installed (or has expired/rotated).
HTTP 418 I'm a teapot
An April Fools’ status from RFC 2324 — some sites and WAFs return it on purpose to tell bots or scrapers to go away.
Nginx 444 No Response (connection closed without response)
An Nginx-specific code: the server deliberately closed the connection without sending anything — a rule is dropping the request.
Cloudflare Error 1009: Access denied — The owner of this website has banned the country or region your IP address is in
The site blocks visitors from your country/region.
AWS: ExpiredToken — The security token included in the request is expired
Temporary AWS credentials (STS/SSO/assumed role) have expired.
OIDC Error: login_required / interaction_required / consent_required (silent authentication failed)
A silent sign-in (prompt=none, iframe or refresh) couldn’t complete because the user must interact — no session, consent needed,…
OAuth callback error: state mismatch / Unable to verify authorization request state / State cookie was missing
The state value returned to the callback doesn’t match what the app stored before redirecting — the CSRF protection for OAuth fai…
Kubernetes: ImagePullBackOff / ErrImagePull
The node can’t pull the container image — wrong name/tag, missing registry credentials, or registry unreachable.
Azure AD (Entra ID): AADSTS700016 Application not found in the directory
The client ID in your sign-in request doesn’t exist in the tenant you’re authenticating against.
HTTP 400 Bad Request
The server could not understand the request because its syntax, headers or body are malformed or invalid.
Warning: Cannot modify header information - headers already sent
You called `header()`, `setcookie()` or `session_start()` after output had already been sent to the browser.
CORS Error: No 'Access-Control-Allow-Origin' header is present
The browser blocked a cross-origin request because the server’s response didn’t include the CORS headers allowing your site’s ori…
HTTP 411 Length Required
The server refuses a request with a body but no Content-Length header.
Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running?
The docker CLI can’t talk to the Docker engine — it isn’t running, or your user can’t access the socket.
HTTP 403 Forbidden
The server understood the request but refuses to authorize it — you (or the server process) are not allowed to access this resour…
OAuth 2.0 Error: invalid_scope / insufficient_scope
The requested scope is unknown or not allowed for this client — or the token lacks the scope the API endpoint requires.
Cloudflare Error 1011: Access denied (Hotlinking denied)
An image or file is being loaded from another site, and Cloudflare Hotlink Protection blocked it.
Cloudflare Turnstile error 110200 / 300030 / 600010 (widget fails to load or verify)
The Turnstile widget couldn’t run or validate — wrong sitekey/domain, blocked scripts, or a client/network issue.
java.lang.SecurityException: Permission Denial ... requires android.permission.X
The app called an API that needs a permission it hasn’t declared or the user hasn’t granted at runtime.
SyntaxError: Unexpected token < in JSON at position 0
`JSON.parse()` / `response.json()` received something that isn’t JSON — very often an HTML error page.
ASP.NET Core: The antiforgery token could not be decrypted / The required antiforgery cookie is not present (400 Bad Request)
Form POST failed antiforgery validation — the token is missing, the cookie is missing, or Data Protection keys changed so old tok…
WordPress: 403 Forbidden on wp-admin, wp-login.php or admin-ajax.php
The server or a security layer refused access to WordPress admin URLs — file permissions, a security plugin/WAF rule, ModSecurity…
ASP.NET Core: The CORS protocol does not allow specifying a wildcard (any) origin and credentials at the same time
The CORS policy uses AllowAnyOrigin() together with AllowCredentials(), which browsers forbid.
AmbiguousMatchException: The request matched multiple endpoints. Matches: X, Y
Two controller actions or minimal API endpoints have the same route and HTTP method.
Bearer error="invalid_token": IDX10223: Lifetime validation failed. The token is expired / IDX10501: Signature validation failed
ASP.NET Core’s JwtBearer middleware rejected the token — expired (IDX10223), signature key not found (IDX10501/IDX10503), or wron…
HTTP 405 Method Not Allowed
The URL exists, but it doesn’t accept the HTTP method you used (e.g. POST to a GET-only route).
AADSTS50053: Your account is locked (Smart Lockout) / sign-in blocked due to suspicious activity
Too many failed sign-ins (or sign-ins from a malicious IP) triggered Entra Smart Lockout.
WordPress: Sorry, you are not allowed to upload this file type / Sorry, this file type is not permitted for security reasons
WordPress blocked the upload because the file extension/MIME type isn’t in its allowed list (SVG, JSON, WEBP on old versions, fon…
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