{"id":"CVE-2026-33410","aliases":["BIT-discourse-2026-33410","EUVD-2026-13341","GHSA-2m5j-6v2r-cq2h"],"status":"published","title":"Discourse hardens chat DM channel creation and expansion","description":"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.","severity":{"version":"3.1","score":5.4,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00166,"percentile":0.05877,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-863"],"published":"2026-03-19T21:57:27Z","modified":"2026-10-28T02:30:34Z","fixes":[{"ecosystem":"Bitnami","package":"discourse","fixed_in":["2026.1.2","2026.2.1","2026.3.0"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Bitnami","package":"discourse","ranges":[{"type":"SEMVER","events":[{"introduced":"2026.1.0"},{"fixed":"2026.1.2"},{"introduced":"2026.2.0"},{"fixed":"2026.2.1"},{"introduced":"2026.3.0"},{"fixed":"2026.3.0"}]}]}],"products":[{"vendor":"discourse","product":"discourse"}],"references":[{"url":"https://github.com/discourse/discourse/security/advisories/GHSA-2m5j-6v2r-cq2h","tags":["x_refsource_CONFIRM","Vendor Advisory","advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-33410","tags":["web","advisory"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/33xxx/CVE-2026-33410.json","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-33410","title":"Discourse hardens chat DM channel creation and expansion","description":"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.","status":"published","published":"2026-03-19T21:57:27.176Z","modified":"2026-03-20T16:11:14.726Z","cvss":[{"version":"3.1","score":5.4,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N","level":"medium","assessor":"cna"}],"cwes":["CWE-863"],"updated_at":"2026-11-02T14:20:08.009733Z"}],"euvd":[{"id":"EUVD-2026-13341","description":"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.","status":"published","published":"2026-03-19T21:57:27Z","modified":"2026-03-20T16:11:14Z","cvss":[{"version":"3.1","score":5.4,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T19:25:32.430758Z"}],"nvd":[{"id":"CVE-2026-33410","description":"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.","status":"published","published":"2026-03-19T22:16:42.827Z","modified":"2026-06-17T10:37:26.793Z","cvss":[{"version":"3.1","score":5.4,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N","level":"medium","assessor":"secondary"},{"version":"3.1","score":5.4,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N","level":"medium","assessor":"primary"}],"cwes":["CWE-863"],"updated_at":"2026-11-02T14:12:10.126802Z"}],"osv":[{"id":"CVE-2026-33410","title":"Discourse hardens chat DM channel creation and expansion","description":"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.","status":"published","published":"2026-03-19T21:57:27.176Z","modified":"2026-10-28T02:30:34.699050851Z","cvss":[{"version":"3.1","score":5.4,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N","level":"medium"}],"cwes":["CWE-863"],"updated_at":"2026-11-02T15:45:01.896044Z"},{"id":"BIT-discourse-2026-33410","title":"Discourse hardens chat DM channel creation and expansion","description":"Discourse is an open-source discussion platform. Versions prior to 2026.3.0, 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, 2026.2.1, and 2026.1.2 contain a patch. No known workarounds are available.","status":"published","published":"2026-03-27T07:11:02.112Z","modified":"2026-09-08T08:46:29.293766496Z","updated_at":"2026-11-02T15:28:29.152062Z"}]}}