CVE-2026-59828

Discourse is an open-source discussion platform. Prior to 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5, post revisions that should be hidden from regular users could be leaked through visible diffs on adjacent revisions serialized by PostRevisionSerializer. This issue is fixed in versions 2026.6.0,...

CVE-2026-49256

Discourse is an open-source discussion platform. Prior to 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5, restricted tag and tag-group names attached to publicly readable categories as allowedtags, allowedtaggroups, or required tag groups could leak to anonymous and unauthorized users through categor...

CVE-2026-53961

Discourse is an open-source discussion platform. Prior to 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5, the AWS SES bounce webhook at POST /webhooks/aws verified that SNS messages were signed by Amazon but did not bind them to trusted TopicArn values, allowing any AWS account holder to publish...

CVE-2026-53962

Discourse is an open-source discussion platform. Prior to 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5, insufficient SVG sanitization in upload and user avatar handling could lead to cross-site scripting when a user visited specific URLs that are not normally part of community browsing. This issue ...

CVE-2026-49256

Discourse is an open-source discussion platform. Prior to 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5, restricted tag and tag-group names attached to publicly readable categories as allowedtags, allowedtaggroups, or required tag groups could leak to anonymous and unauthorized users through categor...

CVE-2026-46413

Discourse is an open-source discussion platform. Prior to 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5, regular users could route direct S3 multipart uploads through ExternalUploadManager into the admin backup store. This issue is fixed in versions 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5...

CVE-2026-53961

CVE-2026-53961 concerns Discourse, an open-source discussion platform. Prior to the fixed versions, the AWS SES bounce webhook at POST /webhooks/aws did not bind SNS-signed messages to trusted TopicArn values, enabling any AWS account holder to publish forged Bounce notifications that revoke a ta...

CVE-2026-55420

Discourse is an open-source discussion platform. Prior to 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5, under certain non-default configurations, processing of PDF uploads could be exploited to obtain RCE on the server. This issue is patched in 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5...

PT-2026-56995

Name of the Vulnerable Software and Affected Versions Discourse versions prior to 2026.6.0 Discourse versions prior to 2026.5.1 Discourse versions prior to 2026.4.2 Discourse versions prior to 2026.1.5 Description Secure uploads may be exposed through the pull hotlinked images function when the...

BIT-DISCOURSE-2026-47264 Discourse: Don't leak restricted tag group names via tag info

Discourse is an open-source discussion platform. From versions 2026.1.0 to before 2026.1.4, 2026.3.0 to before 2026.3.1, and 2026.4.0 to before 2026.4.1, DetailedTagSerializertaggroupnames returned every tag group a tag belonged to without filtering against the requesting user's visibility. With...

BIT-DISCOURSE-2026-44779 Discourse: Bot debug endpoints disclose whisper translation audit logs

Discourse is an open-source discussion platform. From versions 2026.1.0 to before 2026.1.4, 2026.3.0 to before 2026.3.1, and 2026.4.0 to before 2026.4.1, bot debug endpoints disclose whisper translation audit logs. This issue has been patched in versions 2026.1.4, 2026.3.1, 2026.4.1, and 2026.5.0...

CVE-2026-44785

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, the AI "explain" helper only checks cansee? on the post being explained, not its replytopost, so any authenticated user wi...

CVE-2026-45775 Discourse: Cross-site backup access via path traversal in multisite local backups

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, a path traversal vulnerability in Discourse backup handling could allow an authenticated administrator on one site in a...

CVE-2026-44785 Discourse: Hidden reply-to post raw can be disclosed through AI explain prompts

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, the AI "explain" helper only checks cansee? on the post being explained, not its replytopost, so any authenticated user wi...

EUVD-2026-36583

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, bot debug endpoints disclose whisper translation audit logs. This issue has been patched in versions 2026.1.4, 2026.3.1,...

EUVD-2026-36582

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, chat events for public category channels are published to MessageBus without permission scoping, so any MessageBus...

PT-2026-48982

Name of the Vulnerable Software and Affected Versions Discourse versions 2026.1.0 through 2026.1.3 Discourse versions 2026.3.0 Discourse versions 2026.4.0 Description The AI explain helper fails to verify the can see? permission on the reply to post of a post being explained. This allows an...

PT-2026-48979

Name of the Vulnerable Software and Affected Versions Discourse versions 2026.1.0 through 2026.1.3 Discourse versions 2026.3.0 Discourse versions 2026.4.0 Description An issue exists in the GroupPostSerializer where the predicate for the :name attribute was incorrectly declared as include user lo...

CVE-2026-34154

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, a vulnerability in the discourse-subscriptions plugin allows users to gain access to subscription-gated groups without completing payment. This issue has been fixed in version...

CVE-2026-34154

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, a vulnerability in the discourse-subscriptions plugin allows users to gain access to subscription-gated groups without completing payment. This issue has been fixed in version...