CVE-2026-59829: Missing Authorization

Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.1, on sites with category group moderation enabled, the review queue could include an excerpt and permalink of the private message attached to a flag, even when the reviewing category moderator was...

PT-2026-73248

Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, Onebox::DomainChecker.is blocked? compares hostnames and SiteSetting.blocked onebox domains entries case-sensitively, allowing an attacker to bypass configured Onebox domain restrictions by...

PT-2026-73251

Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, plugins/chat/lib/chat/onebox handler.rb resolves Chat::Thread by route thread id independently of the route channel id before checking whether the user can preview the selected chat channel. An...

PT-2026-73254

Discourse is an open-source discussion platform. Prior to 026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, a low-privileged user could place crafted content in the moderation review queue that executed stored cross-site scripting when a moderator viewed it on a site with a modified or disabled default...

PT-2026-73252

Discourse is an open-source discussion platform. Prior to 2026.1.6, the staff action log model rendered unescaped previous and new value fields that could inject stored cross-site scripting into the staff interface. The issue is fixed in 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0...

CVE-2026-53960: Missing Authorization

Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, hidden or otherwise unviewable first-post content was leaked as an excerpt in the publicly-served Q&A QAPage JSON-LD structured data, exposing it to any unauthenticated visitor and to search-engi...

PT-2026-73255

Discourse is an open-source discussion platform. Prior to 2026.1.7, an authenticated user could submit specially formed URLs that bypassed the Onebox allowlist and embedded malicious content in a site. This issue is fixed in versions 2026.1.7, 2026.6.2, 2026.7.1, and 2026.8.0...

PT-2026-73249

Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, TopicLink.extract from, TopicLink.ensure entry for, and TopicLink.duplicate lookup do not consistently enforce Guardian.can see? checks when processing internal links. An authenticated user can...

PT-2026-73250

Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, SiteSerializer.anonymous default navigation menu tags serializes tags from SiteSetting.default navigation menu tags without applying DiscourseTagging.filter visible for the anonymous viewer. An...

CVE-2026-55704: Missing Authorization

Discourse is an open-source discussion platform. Prior o 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, users who were allowed to view a group’s activity, but were not permitted to see shared drafts, could still receive shared-draft entries through the group posts and group mentions endpoints. This...

PT-2026-73256

Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, the discourse-local-dates plugin rendered crafted local-date format data as HTML on sites with a modified or disabled default Content Security Policy. This issue is fixed in versions 2026.1.6,...

PT-2026-73253

Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, an authenticated user could eavesdrop on private AI bot conversations through the AI bot reply stream. The issue is fixed in 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0...

PT-2026-73257

Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, the Rich Text Editor rendered a chat-transcript username as HTML, allowing stored cross-site scripting. This issue is fixed in versions 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0...

PT-2026-73258

Discourse is an open-source discussion platform. From 2026.1.0 until 2026.1.7, 2026.6.2, 2026.7.1, and 2026.8.0, anyone able to run a parameterized Data Explorer query, including non-staff members of a group a query is shared with, could craft parameter values that escaped the intended query and...

PT-2026-76682

Name of the Vulnerable Software and Affected Versions Discourse versions prior to 2026.1.6 Discourse versions prior to 2026.5.2 Discourse versions prior to 2026.6.1 Discourse versions prior to 2026.7.0 Description Users permitted to view group activity but restricted from seeing shared drafts can...

PT-2026-76680

Name of the Vulnerable Software and Affected Versions Discourse versions prior to 2026.1.6 Discourse versions prior to 2026.5.2 Discourse versions prior to 2026.6.1 Discourse versions prior to 2026.7.0 Description Hidden or unviewable first-post content is leaked as an excerpt within the...

PT-2026-73259

Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, the discourse templates endpoint exposed hidden tag names because DiscourseTemplates::TemplatesSerializer in plugins/discourse-templates/app/serializers/discourse templates/templates serializer.r...

PT-2026-73247

Discourse is an open-source discussion platform. Prior to 2026.1.7, 2026.6.2, 2026.7.1, and 2026.8.0, Discourse has HTML injection in PrettyText.format for email because cooked attribute values are reparsed as markup. Crafted Vimeo iframe sources, secure-upload URLs or dimensions, and hashtag...

CVE-2026-55674: Improper Neutralization of Input During Web Page Generation

Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, an unauthenticated attacker could send a single request with a crafted colorschemeid or darkschemeid cookie to inject arbitrary HTML into a Discourse page. Because the cookie value was rendered...

PT-2026-76681

Name of the Vulnerable Software and Affected Versions Discourse versions prior to 2026.1.6 Discourse versions prior to 2026.5.2 Discourse versions prior to 2026.6.1 Discourse versions prior to 2026.7.0 Description An unauthenticated attacker can inject arbitrary HTML into a page by sending a...