{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-33410","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","state":"PUBLISHED","assignerShortName":"GitHub_M","dateReserved":"2026-03-19T17:02:34.171Z","datePublished":"2026-03-19T21:57:27.176Z","dateUpdated":"2026-03-20T16:11:14.726Z"},"containers":{"cna":{"title":"Discourse hardens chat DM channel creation and expansion","problemTypes":[{"descriptions":[{"cweId":"CWE-863","lang":"en","description":"CWE-863: Incorrect Authorization","type":"CWE"}]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":5.4,"baseSeverity":"MEDIUM","confidentialityImpact":"LOW","integrityImpact":"LOW","privilegesRequired":"LOW","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N","version":"3.1"}}],"references":[{"name":"https://github.com/discourse/discourse/security/advisories/GHSA-2m5j-6v2r-cq2h","tags":["x_refsource_CONFIRM"],"url":"https://github.com/discourse/discourse/security/advisories/GHSA-2m5j-6v2r-cq2h"}],"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"}]}],"providerMetadata":{"orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M","dateUpdated":"2026-03-19T21:57:27.176Z"},"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 two authorization issues in the chat direct message API. First, when creating a direct message channel or adding users to an existing one, the `target_groups` parameter was passed directly to the user resolution query without checking group or member visibility for the acting user. An authenticated chat user could craft an API request with a known private/hidden group name and receive a channel containing that group's members, leaking their identities. Second, `can_chat?` only checked group membership, not the `chat_enabled` user preference. A chat-disabled user could create or query DM channels between other users via the direct messages API, potentially exposing private `last_message` content from the serialized channel response. Versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 contain a patch. No known workarounds are available."}],"source":{"advisory":"GHSA-2m5j-6v2r-cq2h","discovery":"UNKNOWN"}},"adp":[{"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-03-20T16:11:06.356952Z","id":"CVE-2026-33410","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-03-20T16:11:14.726Z"}}]}}