Information disclosure in Discourse

CVE-2026-44780

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, ReviewableQueuedPostSerializer unconditionally included payload["raw_email"] for posts that arrived via incoming email. Category moderation group members reaching the review queue could therefore read the full inbound email source (headers, sender trace, MUA, body) without being in view_raw_email_allowed_groups — the trust boundary that gates the dedicated raw-email endpoint. This issue has been patched in versions 2026.1.4, 2026.3.1, 2026.4.1, and 2026.5.0-latest.1.

Vulnerability class: Information Disclosure

EPSS: 0.002 (8.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N.

Affected products

  • Discourse — versions >= 2026.4.0-latest, < 2026.4.1, 2026.5.0, >= 2026.3.0-latest, < 2026.3.1

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-44780?
CVE-2026-44780 is a medium-severity vulnerability in Discourse, classified under Information Disclosure. CVSS score: 4.3/10. Published 2026-06-12.
How severe is CVE-2026-44780?
Medium severity. CVSS v3 base score is 4.3 out of 10.