CVE-2026-28227

Discourse vulnerability

CVSS

2.7

EPSS

3.1%

EPSS pct

86th

Exploited

No known

Discourse is an open source discussion platform. Prior to versions 2025.12.2, 2026.1.1, and 2026.2.0, TL4 users can publish topics into staff-only categories via the `publish_to_category` topic timer, bypassing authorization checks. Versions 2025.12.2, 2026.1.1, and 2026.2.0 patch the issue. No known workarounds are available.

Affected vendor

Discourse

Affected product

Discourse

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:N

Weakness type (CWE)

CWE-863 — Incorrect Authorization

Published

2026-02-26

Risk analysis

Based on its CVSS vector, this vulnerability is exploitable over the network, low attack complexity, requiring high privileges, no user interaction. Successful exploitation leads to low impact to integrity.

Its EPSS score of 3.1% reflects a lower probability of exploitation activity in the wild over the next 30 days, placing it above 86% of all scored CVEs.

Check your external exposure to CVE-2026-28227

Confirm whether Discourse Discourse is running on any internet-facing host or subdomain.
Match discovered service fingerprints against the version affected by CVE-2026-28227.
Prioritise remediation if the asset is public, business-critical, or near authentication/payment flows.

How ThreatPort helps with CVE-2026-28227

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Are you exposed to CVE-2026-28227?

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