{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-121880", "assignerOrgId": "8c484e69-127d-402b-9cdb-5f86ef43eb86", "state": "PUBLISHED", "assignerShortName": "POSIT", "dateReserved": "2026-11-04T10:49:21.246Z", "datePublished": "2026-11-06T15:10:37.306Z", "dateUpdated": "2026-11-06T17:45:27.737Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "8c484e69-127d-402b-9cdb-5f86ef43eb86", "shortName": "POSIT", "dateUpdated": "2026-11-06T15:12:38.657Z"}, "title": "RStudio Server / Posit Workbench localhost port-proxy does not enforce per-session port ownership", "datePublic": "2026-11-04T11:03:00.000Z", "problemTypes": [{"descriptions": [{"lang": "en", "cweId": "CWE-639", "description": "CWE-639 Authorization Bypass Through User-Controlled Key", "type": "CWE"}]}, {"descriptions": [{"lang": "en", "cweId": "CWE-862", "description": "CWE-862 Missing Authorization", "type": "CWE"}]}], "impacts": [{"descriptions": [{"lang": "en", "value": "Information disclosure: an authenticated user can view another user's running application and the data it renders. 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