CVE-2026-33393 Discourse fixes loose hostname matching in spam host allowlist

Discourse is an open-source discussion platform. Prior to versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2, the allowedspamhostdomains check used Stringendwith? without domain boundary validation, allowing domains like attacker-example.com to bypass spam protection when example.com was...