Multiple cross-site request forgery (CSRF) vulnerabilities in Ubiquiti Networks UniFi Controller before 3.2.1 allow remote attackers to hijack the authentication of administrators for requests that (1) create a new admin user via a request to api/add/admin; (2) have unspecified impact via a request to api/add/wlanconf; change the guest (3) password, (4) authentication method, or (5) restricted subnets via a request to api/set/setting/guest_access; (6) block, (7) unblock, or (8) reconnect users by MAC address via a request to api/cmd/stamgr; change the syslog (9) server or (10) port via a request to api/set/setting/rsyslogd; (11) have unspecified impact via a request to api/set/setting/smtp; change the syslog (12) server, (13) port, or (14) authentication settings via a request to api/cmd/cfgmgr; or (15) change the Unifi Controller name via a request to api/set/setting/identity.
Weakness
The web application does not, or can not, sufficiently verify whether a well-formed, valid, consistent request was intentionally provided by the user who submitted the request.
Affected Software
| Name |
Vendor |
Start Version |
End Version |
| Airvision_controller |
Ui |
* |
2.1.3 (including) |
| Mfi_controller |
Ui |
* |
2.0.15 (including) |
| Unifi_controller |
Ui |
* |
3.2.1 (excluding) |
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.
- 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