What is CVE-2026-26979?

CVE-2026-26979 is a low-severity vulnerability in Discourse, classified under Missing Authorization. CVSS score: 2.7/10. Published 2026-02-26.

How severe is CVE-2026-26979?

Low severity. CVSS v3 base score is 2.7 out of 10.

Auth bypass in Discourse

CVE-2026-26979

Discourse is an open source discussion platform. Prior to versions 2025.12.2, 2026.1.1, and 2026.2.0, TL4 users are able to close, archive and pin topics in private categories they don't have access to. Versions 2025.12.2, 2026.1.1, and 2026.2.0 patch the issue. No known workarounds are available.

Vulnerability class: Broken Access Control

EPSS: 0.002 (6.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 2.7 (Low). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:N.

Affected products

Discourse — versions >= 2026.2.0-latest, < 2026.2.0, >= 2026.1.0-latest, < 2026.1.1, 2026.2.0

Weakness classification (CWE)

CWE-862 — Missing Authorization

References

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

Frequently asked questions

What is CVE-2026-26979?: CVE-2026-26979 is a low-severity vulnerability in Discourse, classified under Missing Authorization. CVSS score: 2.7/10. Published 2026-02-26.
How severe is CVE-2026-26979?: Low severity. CVSS v3 base score is 2.7 out of 10.