What is CVE-2026-34154?

CVE-2026-34154 is a medium-severity vulnerability in Discourse, classified under Missing Authorization. CVSS score: 5.3/10. Published 2026-05-19.

How severe is CVE-2026-34154?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Auth bypass in Discourse

CVE-2026-34154

Discourse is an open-source discussion platform. In versions prior to 2026.1.4, 2026.3.1, 2026.4.1 and 2026.5.0-latest.1, a vulnerability in the discourse-subscriptions plugin allows users to gain access to subscription-gated groups witho…

Vulnerability class: Broken Access Control

EPSS: 0.000 (12.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N.

Affected products

Discourse — versions < 2026.1.4, >= 2026.4.0-latest, < 2026.4.1, 2026.5.0

Weakness classification (CWE)

CWE-862 — Missing Authorization

References

security-advisories@github.com (x_refsource_CONFIRM, Mitigation, Vendor Advisory)

Frequently asked questions

What is CVE-2026-34154?: CVE-2026-34154 is a medium-severity vulnerability in Discourse, classified under Missing Authorization. CVSS score: 5.3/10. Published 2026-05-19.
How severe is CVE-2026-34154?: Medium severity. CVSS v3 base score is 5.3 out of 10.