CVE-2026-45780
Discourse: Private event sample invitees are serialized to non-invited event viewers
4.3
MEDIUM
CVSS 3.1
EPSS 0.36%
Description
Discourse is an open-source discussion platform. Prior to 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5, EventSerializer could expose invited group names, sample invitees, and attendance statistics to users who could view the topic but were not entitled to view the private event invitee list. This issue is fixed in versions 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5.
How to fix CVE-2026-45780
To remediate CVE-2026-45780, upgrade the affected package to a fixed version below.
- —upgrade to 2026.1.5 or later
Is CVE-2026-45780 being exploited?
Low — EPSS is 0.4%, meaning exploitation activity has not been observed at scale.
Affected packages (1)
- >= 2026.1.0, < 2026.1.5, >= 2026.4.0, < 2026.4.2, >= 2026.5.0, < 2026.5.1
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | MEDIUM4.3 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N |