CVE-2026-28282

Discourse is an open-source discussion platform. Versions prior to 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 have a security flaw in the discourse-policy plugin which allowed a user with policy creation permission to gain membership access to any private/restricted groups. Once membership to a private/restricted group has been obtained, the user will be able to read private topics that only the group has access to. Versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 contain a patch. As a 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.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/discourse/discourse/commit/64e2514ac17046cfaa8bc68a3c5140bc40736add	Patch
https://github.com/discourse/discourse/commit/c14b8a4cc5fc94e4839a83c5d55765897589f45b	Patch
https://github.com/discourse/discourse/commit/dcde9de530f515e88f99957056ffbcc2e1e03951	Patch
https://github.com/discourse/discourse/security/advisories/GHSA-6cc8-x3rm-j5pf	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:discourse:discourse::::::::
	cpe:2.3:a:discourse:discourse::::::::
	cpe:2.3:a:discourse:discourse:2026.3.0::::latest:::

History

No history.

Information

Published : 2026-03-19 22:16

Updated : 2026-03-23 20:16

NVD link : CVE-2026-28282

Mitre link : CVE-2026-28282

CVE.ORG link : CVE-2026-28282

JSON object : View

Products Affected

discourse

discourse

CWE

CWE-863

Incorrect Authorization

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Versions prior to 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 have a security flaw in the discourse-policy plugin which allowed a user with policy creation permission to gain membership access to any private/restricted groups. Once membership to a private/restricted group has been obtained, the user will be able to read private topics that only the group has access to. Versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 contain a patch. As a 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."}, {"lang": "es", "value": "Discourse es una plataforma de discusi\u00f3n de c\u00f3digo abierto. Las versiones anteriores a 2026.3.0-latest.1, 2026.2.1 y 2026.1.2 tienen una falla de seguridad en el plugin discourse-policy que permit\u00eda a un usuario con permiso de creaci\u00f3n de pol\u00edticas obtener acceso de membres\u00eda a cualquier grupo privado/restringido. Una vez que se ha obtenido la membres\u00eda a un grupo privado/restringido, el usuario podr\u00e1 leer temas privados a los que solo el grupo tiene acceso. Las versiones 2026.3.0-latest.1, 2026.2.1 y 2026.1.2 contienen un parche. Como soluci\u00f3n alternativa, revise todas las pol\u00edticas para el uso de 'add-users-to-group' y elimine temporalmente el atributo de la pol\u00edtica. Alternativamente, deshabilite el plugin discourse-policy deshabilitando la configuraci\u00f3n del sitio 'policy_enabled'."}], "lastModified": "2026-03-23T20:16:43.230", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "4BE96625-3609-410C-B41E-4A824C1A57C0", "versionEndExcluding": "2026.1.2", "versionStartIncluding": "2026.1.0"}, {"criteria": "cpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "FD31CF04-CF2F-4FB9-8880-9243BC7671A7", "versionEndExcluding": "2026.2.1", "versionStartIncluding": "2026.2.0"}, {"criteria": "cpe:2.3:a:discourse:discourse:2026.3.0:*:*:*:latest:*:*:*", "vulnerable": true, "matchCriteriaId": "E3FE9277-4F6B-4FD0-991F-F0FB8D226E1C"}], "operator": "OR"}]}], "sourceIdentifier": "security-advisories@github.com"}