BIT-DISCOURSE-2026-72725 Discourse: Stored XSS in staff action logs injects staff UI

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...

BIT-DISCOURSE-2026-72724 Discourse: Private Chat Threat Message Disclosure via Chat Onebox Channel/Threat ID Mismatch

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/oneboxhandler.rb resolves Chat::Thread by route threadid independently of the route channelid before checking whether the user can preview the selected chat channel. An...

BIT-DISCOURSE-2026-72723 Discourse: Anonymous sidebar serialization exposes descriptions of category-restricted tags

Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, SiteSerializer.anonymousdefaultnavigationmenutags serializes tags from SiteSetting.defaultnavigationmenutags without applying DiscourseTagging.filtervisible for the anonymous viewer. An...

BIT-DISCOURSE-2026-72722 Discourse: Duplicate lookup reveals restricted topic titles through canonicalized URLs

Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, TopicLink.extractfrom, TopicLink.ensureentryfor, and TopicLink.duplicatelookup do not consistently enforce Guardian.cansee? checks when processing internal links. An authenticated user can submit...

BIT-DISCOURSE-2026-72721 Discourse: Onebox Domain Blocklist Bypass via Case-Sensitive Comparison

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

BIT-DISCOURSE-2026-72720 Discourse: HTML injection in PrettyText.format_for_email from cooked-attribute reparsing

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.formatforemail because cooked attribute values are reparsed as markup. Crafted Vimeo iframe sources, secure-upload URLs or dimensions, and hashtag...

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-2026-76681

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...

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-2026-76683

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 2026.7.1 Description On sites with category group moderation enabled, the review queue may expose an...

CVE-2026-72732

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

CVE-2026-72732

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

CVE-2026-72732

Discourse contains a vulnerability in the discourse_templates endpoint where hidden tag names could be exposed due to an inadequate filter in DiscourseTemplates::TemplatesSerializer; this allowed users to view tags they should not see. The issue affects prior to 2026.1.6, 2026.5.2, 2026.6.1, and ...

CVE-2026-72732 Discourse: Templates endpoint exposes hidden tag names

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

CVE-2026-72732 Discourse: Templates endpoint exposes hidden tag names

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

CVE-2026-72728

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-latest.1...

CVE-2026-72729

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,...

CVE-2026-72731

Discourse is an open-source discussion platform. From 2026.1.0-latest until 2026.1.7, 2026.6.2, 2026.7.1, and 2026.8.0-latest.1, 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...

CVE-2026-72730

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...

CVE-2026-72727

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...