A missing check for IPv4 nested inside IPv6 in Nextcloud server < 17.0.1, < 16.0.7, and < 15.0.14 allowed a Server-Side Request Forgery (SSRF) vulnerability when subscribing to a malicious calendar URL.
Weakness
The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Nextcloud_server | Nextcloud | * | 15.0.14 (excluding) |
| Nextcloud_server | Nextcloud | 16.0.0 (including) | 16.0.7 (excluding) |
| Nextcloud_server | Nextcloud | 17.0.0 (including) | 17.0.2 (excluding) |