{"id":"CVE-2026-28282","state":"PUBLISHED","title":"Discourse vulnerable to group membership addition permission bypass via discourse-policy plugin","description":"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.","publishedAt":"2026-03-19T21:45:13.648Z","updatedAt":"2026-03-20T18:10:26.922Z","severity":{"score":2.3,"label":"Low","version":"4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["discourse discourse"],"affected":[{"vendor":"discourse","product":"discourse","versions":[{"version":">= 2026.1.0-latest, < 2026.1.2","status":"affected"},{"version":">= 2026.2.0-latest, < 2026.2.1","status":"affected"},{"version":"= 2026.3.0-latest","status":"affected"}]}],"references":["https://github.com/discourse/discourse/security/advisories/GHSA-6cc8-x3rm-j5pf","https://github.com/discourse/discourse/commit/64e2514ac17046cfaa8bc68a3c5140bc40736add","https://github.com/discourse/discourse/commit/c14b8a4cc5fc94e4839a83c5d55765897589f45b","https://github.com/discourse/discourse/commit/dcde9de530f515e88f99957056ffbcc2e1e03951"],"weaknesses":["CWE-863"],"ingestedAt":"2026-10-29T20:11:31.369Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/28xxx/CVE-2026-28282.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-28282","state":"PUBLISHED","datePublished":"2026-03-19T21:45:13.648Z","dateUpdated":"2026-03-20T18:10:26.922Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-02-26T01:52:58.735Z"},"containers":{"cna":{"title":"Discourse vulnerable to group membership addition permission bypass via discourse-policy plugin","descriptions":[{"lang":"en","value":"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."}],"affected":[{"vendor":"discourse","product":"discourse","versions":[{"version":">= 2026.1.0-latest, < 2026.1.2","status":"affected"},{"version":">= 2026.2.0-latest, < 2026.2.1","status":"affected"},{"version":"= 2026.3.0-latest","status":"affected"}]}],"references":[{"url":"https://github.com/discourse/discourse/security/advisories/GHSA-6cc8-x3rm-j5pf","name":"https://github.com/discourse/discourse/security/advisories/GHSA-6cc8-x3rm-j5pf","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/discourse/discourse/commit/64e2514ac17046cfaa8bc68a3c5140bc40736add","name":"https://github.com/discourse/discourse/commit/64e2514ac17046cfaa8bc68a3c5140bc40736add","tags":["x_refsource_MISC"]},{"url":"https://github.com/discourse/discourse/commit/c14b8a4cc5fc94e4839a83c5d55765897589f45b","name":"https://github.com/discourse/discourse/commit/c14b8a4cc5fc94e4839a83c5d55765897589f45b","tags":["x_refsource_MISC"]},{"url":"https://github.com/discourse/discourse/commit/dcde9de530f515e88f99957056ffbcc2e1e03951","name":"https://github.com/discourse/discourse/commit/dcde9de530f515e88f99957056ffbcc2e1e03951","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"PRESENT","privilegesRequired":"LOW","userInteraction":"NONE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"LOW","vulnAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","baseScore":2.3,"baseSeverity":"LOW","vectorString":"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N","version":"4.0"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-863","lang":"en","description":"CWE-863: Incorrect Authorization","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-03-19T21:48:54.093Z"},"source":{"advisory":"GHSA-6cc8-x3rm-j5pf","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-03-20T17:00:56.189009Z","id":"CVE-2026-28282","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-03-20T18:10:26.922Z"}}]}}}