PT-2026-26378 · Discourse · Discourse+1

Lowdavidtaylorhq · Published 2026-03-19 · Updated 2026-03-27 · CVE-2026-28282

Positive Technologies (AI Summary)

CVSS v3.1

6.5

Medium

Base vector

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

Name of the Vulnerable Software and Affected Versions Discourse versions prior to 2026.3.0-latest.1 Discourse versions prior to 2026.2.1 Discourse versions prior to 2026.1.2

Description Discourse is an open-source discussion platform. A security flaw exists within the discourse-policy plugin that allows a user with policy creation permissions to gain membership access to any private or restricted groups. Once a user obtains membership to a private or restricted group, they can read private topics accessible only to that group. The flaw involves the add-users-to-group attribute within policies.

Recommendations Versions prior to 2026.3.0-latest.1: Update to version 2026.3.0-latest.1 or later. Versions prior to 2026.2.1: Update to version 2026.2.1 or later. Versions prior to 2026.1.2: Update to version 2026.1.2 or later. As a temporary workaround, review all policies for the use of add-users-to-group and temporarily remove the attribute from the policy. Alternatively, disable the discourse-policy plugin by disabling the policy enabled site setting.

Exploit

Fix

Incorrect Authorization

Weakness Enumeration

CWE-863

Related Identifiers

BIT-DISCOURSE-2026-28282

CVE-2026-28282

GHSA-6CC8-X3RM-J5PF

Affected Products

Discourse

Discourse-Policy

References · 10

• 🔥 https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/28xxx/CVE-2026-28282.json · Exploit
• https://github.com/discourse/discourse/security/advisories/GHSA-6cc8-x3rm-j5pf · Vendor Advisory
• https://github.com/discourse/discourse/commit/64e2514ac17046cfaa8bc68a3c5140bc40736add · Patch
• https://github.com/discourse/discourse/commit/dcde9de530f515e88f99957056ffbcc2e1e03951 · Patch
• https://github.com/discourse/discourse/commit/c14b8a4cc5fc94e4839a83c5d55765897589f45b · Patch
• https://osv.dev/vulnerability/CVE-2026-28282 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-28282 · Security Note
• https://osv.dev/vulnerability/BIT-discourse-2026-28282 · Vendor Advisory
• https://twitter.com/infoflowcloud/status/2034892972743946491 · Twitter Post
• https://twitter.com/CVEnew/status/2034891624568746494 · Twitter Post