CVE-2026-72724

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...

CVE-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...

CVE-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...

EUVD-2026-55663

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...

CVE-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...

EUVD-2026-55660

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...

CVE-2026-72723

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...

CVE-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...

CVE-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...

CVE-2026-72723

CVE-2026-72723 (Discourse) : The issue affects Discourse versions prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0. SiteSerializer.anonymous_default_navigation_menu_tags exposes tag names and descriptions for tags restricted by categories, category tag groups, or tag-group permissions to unaut...

CVE-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...

CVE-2026-72722

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...

CVE-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...

CVE-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...

CVE-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...

CVE-2026-72722

Discourse (open‑source discussion platform) contains a vulnerability in TopicLink processing prior to versions 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0. The affected components are TopicLink.extract_from, TopicLink.ensure_entry_for, and TopicLink.duplicate_lookup. The root cause is that Guardia...

EUVD-2026-55659

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...

CVE-2026-72721

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...

CVE-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...

EUVD-2026-55657

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...