# CVE-2026-72726: Discourse AI bot reply stream information disclosure

Source: https://junglewise.ai/threats/cve-2026-72726-discourse-ai-bot-reply-stream-information-disclosure  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-10. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-72726 · Severity: medium · CVSS 6.5 · Published 2026-08-10

Discourse is an open-source discussion platform that includes AI bot features. An authenticated user could eavesdrop on private AI bot conversations through the reply stream mechanism, potentially exposing sensitive discussions between other users and AI bots. This allows unauthorized access to private conversation content.

Technologies: [Discourse](https://junglewise.ai/threats/technologies/discourse). Vendors: [Discourse](https://junglewise.ai/threats/vendors/discourse).

## Quick answers

**Is CVE-2026-72726 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-72726 being exploited in the wild.

**How severe is CVE-2026-72726?** Medium severity, with a CVSS score of 6.5, published 10 August 2026.

**Which products and versions are affected?** Discourse Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0.

**Is there a fix for CVE-2026-72726?** A patch was published on 2026-07-28: Security fixes committed to repository Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-72726 attacked?** It is attacked over the network, in a web application.

**Am I affected by CVE-2026-72726?** Check whether you run Discourse at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

This vulnerability is an authorization/access control issue in the AI bot reply streaming functionality. Authenticated users could access private messages (PMs) containing AI bot replies even when they were not participants in those conversations. The root cause was insufficient scoping of the reply stream to only include PM participants. The fix, implemented in the patched versions, restricts the reply stream visibility by scoping it to the private message's actual participants through stream_user_ids and stream_group_ids variables. No authentication bypass is required—the attacker must be an authenticated user, but network access is sufficient for exploitation.

## Affected products

- Discourse Discourse Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0

## Timeline

- 2026-08-10: disclosed
- 2026-07-28: patched: Security fixes committed to repository

## References

- [https://github.com/discourse/discourse/commit/01faa889830f56e02fba2f6c1731811d319c5e81](https://github.com/discourse/discourse/commit/01faa889830f56e02fba2f6c1731811d319c5e81)
- [https://github.com/discourse/discourse/commit/1fb2026eb8004dfeb12553014cc534dfd8083fbc](https://github.com/discourse/discourse/commit/1fb2026eb8004dfeb12553014cc534dfd8083fbc)

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