CVE-2026-27935 Discourse leaks private topic metadata to non-authorized users

What is CVE-2026-27935?

CVE-2026-27935 is a medium-severity vulnerability in Discourse Discourse, published on 19 Mar 2026. An attacker needs administrator access to exploit it, with no action from the victim.

Official description

Discourse is an open-source discussion platform. Versions prior to 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 have a vulnerability in an API endpoint that discloses private topic metadata of admin users to moderator users even if the moderators do not have access to the private topics. Versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 contain a patch. No known workarounds are available.

Weakness: CWE-201

Which versions are affected by CVE-2026-27935?

1 open source package ship an affected version, including discourse. It affects 1 product.

Products include Discourse Discourse.

How do I fix CVE-2026-27935?

Upgrade discourse to a fixed version for your release line: 2026.1.2, 2026.2.1 or 2026.4.0.

Is CVE-2026-27935 being exploited?

There is no known exploitation of CVE-2026-27935 in the wild and no public exploit code.

Other vulnerabilities in Discourse Discourse

• CVE-2021-41163 RCE via malicious SNS subscription payload Critical 10.0
• CVE-2022-36066 Discourse vulnerable to RCE via admins uploading maliciously zipped file Critical 9.1
• CVE-2022-39356 Discourse user account takeover via email and invite link High 8.9
• CVE-2023-22468 Discourse vulnerable to Cross-site Scripting in local oneboxes High 8.8
• CVE-2026-27934 Discourse leaks private topic title and post excerpt via user action API endpoint High 8.7

All Discourse Discourse vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as BIT-discourse-2026-27935, GHSA-wxqr-r4wv-cw76.