CSRF Protection
Сross-Site Request Forgery (CSRF) protection in TeamCity implies a number of requirements on HTTP requests.
Since version 2020.1, TeamCity uses only CSRF tokens as a protection measure. In previous versions of TeamCity, Origin/Referer headers were also used.
To obtain a security token, send the GET https://your-server/authenticationTest.html?csrf request.
To pass the token, use the X-TC-CSRF-Token HTTP request header or the tc-csrf-token HTTP parameter.
CSRF checks for HTTP request
When considering HTTP request safety from the TeamCity perspective, the following checks are sequentially made:
If an HTTP request is a non-modifying one (such as
GET), it is considered safe.If an HTTP request has a secure CSRF token either in the parameter or in the HTTP header and this token matches the one stored in user session, it is considered safe.
Implications for non-browser HTTP clients
For non-browser API access, we recommend using token-based authentication.
Implications for CORS clients
To use CORS request, configure the CORS support as described here. This configuration will be enough for GET requests.
If you need to send POST/PUT/DELETE requests via CORS, you should obtain a CSRF token using the authenticationTest.html?csrf call, and then provide this token with your modifying HTTP requests.
Troubleshooting
If you face problems regarding CSRF protection in TeamCity, please contact our support.