CVE-2020-8138
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. Date published : 2020-03-20 https://nextcloud.com/security/advisory/?id=NC-SA-2020-014