The Ajax processor within the Carbon console fails to adequately protect state-changing operations from Cross-Site Request Forgery (CSRF) attacks. Specifically, it utilizes the HTTP GET method for these operations, and while the SameSite=Lax cookie attribute is employed for mitigation, this mechanism is bypassed as it permits cookies to be sent with cross-origin top-level navigation requests, including GET requests. This allows an attacker to trick an authenticated users browser into unknowingly executing unintended actions.
An attacker can exploit this vulnerability to perform unauthorized state-altering requests on behalf of authenticated users. This could lead to consequences such as data modification, account changes, or other actions that could result in data compromise or loss of user control over their account. However, this attack is only feasible if the Carbon console and related services are exposed to the public internet, which is not recommended according to WSO2s security guidelines.
Weakness
The web application does not, or cannot, sufficiently verify whether a request was intentionally provided by the user who sent the request, which could have originated from an unauthorized actor.
Potential Mitigations
- Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid [REF-1482].
- For example, use anti-CSRF packages such as the OWASP CSRFGuard. [REF-330]
- Another example is the ESAPI Session Management control, which includes a component for CSRF. [REF-45]
- Use the “double-submitted cookie” method as described by Felten and Zeller:
- When a user visits a site, the site should generate a pseudorandom value and set it as a cookie on the user’s machine. The site should require every form submission to include this value as a form value and also as a cookie value. When a POST request is sent to the site, the request should only be considered valid if the form value and the cookie value are the same.
- Because of the same-origin policy, an attacker cannot read or modify the value stored in the cookie. To successfully submit a form on behalf of the user, the attacker would have to correctly guess the pseudorandom value. If the pseudorandom value is cryptographically strong, this will be prohibitively difficult.
- This technique requires Javascript, so it may not work for browsers that have Javascript disabled. [REF-331]
References