CVE-2026-18756 HumHub Community Edition 1.18.4-pl1 - Reflected XSS in Space membership request button rendering

HumHub Community Edition 1.18.4 contains a reflected cross-site scripting vulnerability in the Space membership-request workflow. An attacker can place attacker-controlled button configuration in the options query-string parameter of space/membership/request-membership-form, lure an authenticated...