Home Search Pricing Get inErrata About

Sign in Sign up

Graph/cross-site-cookie-rejection-url-mismatch

Pattern

Cross-Site Cookie Rejection

cross-site-cookie-rejection-url-mismatch

A recurring mismatch where HTTPS vs HTTP (and SameSite/Secure) diverge across redirect and deployment contexts, causing browsers to reject cookies or mixed-content blocking until URLs, domains, and cookie attributes are aligned.

Node Details

Public graph metadata

Updated4/30/2026

Connections

30 linked nodes

Cookie “__vercel_live_token” has been rejected because it is in a cross-site context and its “SameSite” is “Lax” or “Strict” — deployed it on Vercel. Tension: But i setup cookies in my project like this. Outcome: Then you need to use https://localhost:5000 and not http://localhost:5000.

When the UI calls the `POST /auth/callback/passkey` endpoint. Tension: Origin servers SHOULD NOT fold multiple Set-Cookie header fields into a single header field. Outcome: Cloudflare seem to be in the wrong here.

when I refresh my page the cookie gets deleted — I have deployed my sveltekit frontend and python flask backend on vercel. Tension: On localhost, they worked just fine however when I deployed it, the cookies were not persistent. Outcome: it does sets the cookie, but on refresh, the cookie gets disappeared.

Refused to load the script 'https://conoret.com/dsp?h=car-doctor-server-bay-rho.vercel.app&r=0.47386382518756887' because it violates the following Content Security Policy directive: "default-src 'none'" — I deployed my serversite code in vercel, but my site replied with status code 404. Tension: Note that 'script-src-elem' was not explicitly set, so 'default-src' is used.

This particular set of mysterious errors has been asked about on Sentry's GitHub — they reference a WebKit issue. Tension: they are caused by an error coming from a Safari browser extension. Outcome: can safely be ignored, or filtered.

it fails — The code works locally but when I put it on an EC2 machine and change the CORS origins accordingly. Tension: I've checked the URL for 2 hours straight. Outcome: Still the same error below.

Using Fetch from my `index.html` from my `portal.mydomain.com` does not. — Enter `api.mydomain.com` into a browser directly does save my cookie. Tension: I have no CORS errors and the OPTIONS, GET and POST requests all get a 200 response. Outcome: just no cookie, nor can I see the cookie set in my broswer dev tools.

none of customized request headers could be obtained in `UserIdValidationMiddleware` — If the order is reversed, then. Tension: It is not on the axios side. Outcome: Finally, this issue is fixed after reading CORSMiddleware not work and it is related to CORS.

When deployed on Azure App Service behind a proxy, FastAPI/Starlette redirects requests to an HTTP URL (e.g., HTTP Location header in a 307) instead of preserving HTTPS. This causes browser mixed-content/security failures because the app is loaded over HTTPS but redirected to HTTP.

RedirectResponse goes to "/" without the authentication cookie

AADSTS9002325: Proof Key for Code Exchange is required for cross-origin authorization code redemption. Tension: redirects uris not matching.

SessionMiddleware in a FastAPI backend fails to set the session cookie when the React frontend and backend are hosted on different domains/subdomains (e.g., XXX-ui.fly.dev vs XXX-api.fly.dev). The browser rejects the cookie with an 'invalid domain' error and no session is maintained.

were not accessible in js and in browser — Cookies are being set and sent with the next request. Outcome: The problem solved by adding `domain="blueberry.adefe.xyz"` to the cookie in response.

Chrome at least, blocks concurrent GET reuqests on the same URL — Testing with one Chrome in Incognito should work. Outcome: it worked.

The Stripe/hCaptcha script fails to load due to a Content Security Policy violation: inline script execution is blocked under `script-src 'self'`.

The someone can easily append this query string to end of the page or fake the http referer to pretende to have paid for the product — in my getServerSideProps() function in my page, which is redirect from check out as determined by success_url. Tension: I need a server side check too. Outcome: How can I do that?

Checkout redirect can be faked by appending the success query string or spoofing the HTTP referer

Refused to evaluate a string as JavaScript because 'unsafe-eval' is not an allowed source of script. Tension: I didn't set any CSPs for my app.

MissingKeyMissing Key-Pair-Id query parameter or cookie value — {urn}/manifest/{derivativeurn}/signedcookies. Tension: I get the following error that suggest I'm missing a header.

In an Electron renderer process, cross-origin fetches behave differently in development vs production, with no expected CORS preflight requests visible in production builds. The user also questions whether Electron enforces browser-style CORS and how `nodeIntegration` affects this behavior.

the cookie will be specifically set with `domain=app.sunsetland.com.au`. Tension: if we were to host another subdomain aside from `app.`, we actually would likely encounter the reCAPTCHA challenge again.

REST API rejects browser client requests when Content Security Policy is not configured to allow the requesting site

Client-side double-submit CSRF token generation is vulnerable to subdomain hijacking

Confusion about cookie authentication versus token authentication

httpOnly cookies are the best way to store tokens safely and protect them from XSS attacks — storing JWTs on the client. Tension: JavaScript won't be allowed to read httpOnly cookies. How would the client handle routes authentication? Outcome: The browser won't automatically set the `Authorization` header like it does with cookies.

the browser prevents a potential CSRF attack and doesn't include the token — The call is to the backend endpoint specified earlier in `redirect_uri`. Tension: I need a browser to include the `ASP.NET_SessionId` cookie in the request. Outcome: If I set the `SameSite` cookie attribute to `None` the endpoint can be reached.

Browsers started logging a Content Security Policy (CSP) violation indicating that requests to https://vortex.data.microsoft.com/collect/v1 were refused because the page’s connect-src directive does not allow that endpoint.

on Chrome I get an error saying that the CSRF token is mismatched — show a third-party web page (with their approval) in an iframe. Tension: This site has a different domain to my parent site. Outcome: The site displays fine on firefox.

If I check 'Remember Me' in form, this add a cookie with name "REMEMBERME". Tension: I'm implementing custom authenticator. Outcome: your cookie is normal.

SecurityError: Error #2121: Security sandbox violation: LoaderInfo.content: file:///C|/Users/Admin/Desktop/whatever.swf cannot access https://content.mspcdns.com/swf/headwear/story_2022_girlhat_tk.swf. — when I run my swf locally (also doesn't work with browser). Tension: I searched on the internet to fix the security problem with allow domain, but it is still not working. Outcome: I don't know what to do!

[inerrata]Tags Knowledge Graph Docs About Pricing Contact Report a Bug Privacy Terms Cookie Settings Do Not Sell or Share My Info

© 2026 Inerrata

Cross-Site Cookie Rejection - inErrata Knowledge Graph | Inerrata