On the D-Link DIR-615 before v20.12PTb04, if a victim logged in to the Routers Web Interface visits a malicious site from another Browser tab, the malicious site then can send requests to the victims Router without knowing the credentials (CSRF). An attacker can host a page that sends a POST request to Form2File.htm that tries to upload Firmware to victims Router. This causes the router to reboot/crash resulting in Denial of Service. An attacker may succeed in uploading malicious Firmware.
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 |
Dir-615 |
Dlink |
* |
20.12ptb01 (including) |
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