CVE-2026-70556

CVE-2026-70556 is a medium-severity vulnerability rated 4.3/10 on the CVSS scale. Hubzilla versions prior to 11.4 contains a cross-site request forgery vulnerability in the OAuth2 /authorize endpoint handled by Zotlabs\Module\Authorize::post() that allows unauthenticated attackers to register arbitrary OAuth2 applications under an authenticated user's account by submitting a cross-origin POST request without CSRF token or Origin/Referer validation. Attackers can craft a malicious HTML form that autosubmits attacker-chosen OAuth2 parameters including client_id, client_secret, redirect_uri, and scope to silently register a persistent OAuth2 application, enabling interception of future OAuth2 authorization codes when the victim later authenticates against the attacker-controlled client.. EPSS estimates a 0.19% chance of exploitation in the next 30 days.