{"schema":"threatline.record/2","record":{"id":"CVE-2026-103858","aliases":[],"summary":"MISP Incomplete Thread Authorization Allows Unauthorized Read and Post Access to Discussions","details":"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","categories":["Unclassified"],"product":"MISP","vendor":"MISP","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-103858","source_modified_at":"2026-10-01T15:00:57.587Z","fetched_at":"2026-10-23T18:52:38.922436Z","product":"MISP","vendor":"MISP","versions":[{"lessThan":"2.5.48","status":"affected","version":"unspecified","versionType":"semver"}],"defaultStatus":null}],"fixed_versions":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-103858","source_modified_at":"2026-10-01T15:00:57.587Z","fetched_at":"2026-10-23T18:52:38.922436Z","package":{"name":"MISP","ecosystem":null},"version":"2.5.48","basis":"first unaffected version stated in the CVE record"}],"cvss":5.3,"severity":"Medium","kev":{"listed":false},"epss":{"probability":0.00219,"percentile":0.11724,"score_date":"2026-10-23"},"published_at":"2026-10-01T11:31:32.840Z","modified_at":"2026-10-01T15:00:57.587Z","provenance":[{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-103858","fetched_at":"2026-10-23T18:52:38.922436Z","source_modified_at":"2026-10-01T15:00:57.587Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-103858","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23"}],"sources":["CVE List","EPSS"],"references":[{"source":"CVE List","url":"https://github.com/MISP/MISP/commit/79fbd4c75","tags":["patch"]}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","cvss_source":"CVE List","ssvc":{"exploitation":"none","automatable":"no","technical_impact":"partial","assessed_at":"2026-10-01T15:00:37.761849Z"},"classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":null,"confidence":"unknown","reviewed":false},"change_timestamp":"2026-10-01T15:00:57.587Z","content_hash":"7885461e8465dd8f43e70c912c7ddcaef70baaa22b5ba82492218ef0603b681b"}}