Nextcloud News <=28.3.0-beta.1 Blind SSRF via Feed URL
CVE-2026-44515 Published on May 14, 2026
Nextcloud News: Authenticated blind SSRF via feed URL
Nextcloud News is an RSS/Atom feed reader. Prior to 28.3.0-beta.1, Nextcloud News allows authenticated users to add feeds by providing a feed URL (via the web interface or the API). In affected versions, an authenticated attacker could provide a URL pointing to internal/private IP ranges or localhost, causing the Nextcloud server to perform server-side HTTP requests to attacker-controlled destinations, but not relaying the result. This enables blind SSRF, which can be used to scan or probe internal network services that are reachable from the Nextcloud server. This vulnerability is fixed in 28.3.0-beta.1.
Weakness Type
What is a SSRF Vulnerability?
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. By providing URLs to unexpected hosts or ports, attackers can make it appear that the server is sending the request, possibly bypassing access controls such as firewalls that prevent the attackers from accessing the URLs directly. The server can be used as a proxy to conduct port scanning of hosts in internal networks, use other URLs such as that can access documents on the system (using file://), or use other protocols such as gopher:// or tftp://, which may provide greater control over the contents of requests.
CVE-2026-44515 has been classified to as a SSRF vulnerability or weakness.