CVE-2026-47263: Discourse: Prevent webhook payload disclosure on event redelivery
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 MessageBus.publish call for /webhookevents/<id> in Jobs::RedeliverWebHookEvents did not pass groupids, leaving the channel readable by any authenticated user (or anonymous user on instances where loginrequired is disabled). Webhook IDs are sequential integers and trivially enumerable. This issue has been patched in versions 2026.1.4, 2026.3.1, 2026.4.1, and 2026.5.0-latest.1.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
discourse/discourseto a version that resolves this vulnerability.Fixed in 2026.1.4 - Upgrade
Upgrade
discourse/discourseto a version that resolves this vulnerability.Fixed in 2026.3.1 - Upgrade
Upgrade
discourse/discourseto a version that resolves this vulnerability.Fixed in 2026.4.1 - Upgrade
Upgrade
discourse/discourseto a version that resolves this vulnerability.Fixed in 2026.5.0-latest.1
Event History
Frequently Asked Questions
What is the severity of CVE-2026-47263?
The severity of CVE-2026-47263 is medium with a score of 4.3.
What does CVE-2026-47263 affect?
CVE-2026-47263 affects Discourse versions from 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.
What is the main issue described in CVE-2026-47263?
CVE-2026-47263 describes an info leak due to insufficient handling of group_ids during the MessageBus.publish call for webhook events.
How do I fix CVE-2026-47263?
To fix CVE-2026-47263, upgrade your Discourse instance to version 2026.1.4, 2026.3.1, or 2026.4.1 or later.
What potential impact does CVE-2026-47263 pose?
CVE-2026-47263 could lead to unauthorized disclosure of webhook payload information.