{"id":"CVE-2026-103858","published":"2026-10-01T12:17:16.080","lastModified":"2026-10-01T15:17:29.540","description":"MISP contains an incomplete authorization check in the discussion posting functionality. When a user submits a post to a thread or replies to an existing post, the application only verified whether the target thread was restricted to a single organization (org-only distribution). It did not enforce the full thread access control list, including sharing-group membership and event-level visibility.\n\nAs a result, an authenticated user who is outside the relevant sharing group or who does not have visibility on the associated event could:\n\n- Read the thread title and the content of the quoted post\n\n- Submit a new post into the discussion thread\n\nThis constitutes both an information disclosure (reading restricted thread and post content) and an integrity issue (injecting content into a thread the user is not authorized to participate in).\n\nAffected: <2.5.48","cvssScore":null,"cvssSeverity":null,"cvssVector":null,"cwes":["CWE-285"],"vendors":[],"products":[],"references":[{"url":"https://github.com/MISP/MISP/commit/79fbd4c75","tags":[]}],"exploitRefs":[{"url":"https://github.com/MISP/MISP/commit/79fbd4c75","tags":[]}],"hasPoc":true,"ai":null}