Discourse: Cached outdated summaries can leak removed content

Discourse is an open-source discussion platform. In versions prior to 2026.1.4, 2026.3.1, 2026.4.1 and 2026.5.0-latest.1, outdated cached AI summaries can leak removed content to anonymous and unprivileged users who cannot regenerate summaries. This issue has been fixed in versions 2026.1.4, 2026.3.1, 2026.4.1 and 2026.5.0-latest.1. To work around this issue, restrict summary generation by tightening the allowed groups on the summarization Personas.