CVE-2026-47264
Description
Discourse is an open-source discussion platform. From versions 2026.1.0-latest to before 2026.1.4, 2026.3.0-latest to before 2026.3.1, and 2026.4.0-latest to before 2026.4.1, DetailedTagSerializer#tag_group_names returned every tag group a tag belonged to without filtering against the requesting user's visibility. With SiteSetting.tags_listed_by_group enabled, anonymous and unprivileged users hitting TagsController#info (which is exempt from requires_login) could read the names of tag groups restricted to specific user groups or non-visible categories. This issue has been patched in versions 2026.1.4, 2026.3.1, 2026.4.1, and 2026.5.0-latest.1.
How to fix
- discourse discourse2026.1.0, 2026.1.4, 2026.3.1, 2026.4.1 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| discourse discourse | v < 2026.1.0, 2026.1.0 ≤ v < 2026.1.4, 2026.3.0 ≤ v < 2026.3.1, 2026.4.0 ≤ v < 2026.4.1, 2026.5.0 | 2026.1.0, 2026.1.4, 2026.3.1, 2026.4.1 |
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Attack Surface Management
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