{"id":"CVE-2026-42862","aliases":["GHSA-x5v6-pj28-cwwm"],"url":"https://o3.security/vulnerability/CVE-2026-42862","summary":"Flowise: Mass Assignment in Tool Update Endpoint Allows Cross-Workspace Resource Reassignment","details":"### Summary\nA Mass Assignment vulnerability exists in the tool update endpoint of FlowiseAI.\n\nThe endpoint allows authenticated users to modify server-controlled properties such as workspaceId, createdDate, and updatedDate when updating a tool resource.\n\nDue to missing server-side validation and authorization checks, an attacker can manipulate the workspaceId field and reassign tools to arbitrary workspaces. This breaks tenant isolation in multi-workspace environments.\n\n### Details\nThe endpoint responsible for updating tools:\n\n**PUT /api/v1/tools/{toolId}**\n\naccepts a JSON request body containing tool metadata.\n\nHowever, the server does not restrict which properties may be modified by the client. As a result, user-controlled request bodies can include additional fields that should normally be controlled only by the backend.\n\nServer-controlled fields that can be manipulated include:\n\n1. workspaceId\n2. createdDate\n3. updatedDate\n\nThe request body is directly merged into the underlying database entity without proper DTO validation or authorization checks.\n\n### PoC\nAuthenticate to the Flowise interface.\n\nCapture the request used to update a tool:\n\n```http\nPUT /api/v1/tools/<TOOL_ID>\nContent-Type: application/json\n\nModify the request body by injecting additional fields:\n\n{\n  \"name\": \"aaa\",\n  \"description\": \"bbb\",\n  \"color\": \"linear-gradient(rgb(109,215,45), rgb(136,170,134))\",\n  \"schema\": \"[]\",\n  \"func\": \"\",\n  \"iconSrc\": \"test\",\n  \"workspaceId\": \"11111111-2222-3333-4444-555555555555\",\n  \"createdDate\": \"1995-03-06T14:17:50.000Z\",\n  \"updatedDate\": \"1995-03-06T14:17:50.000Z\"\n}\n\n```\nSend the request.\n\nObserve that the response includes the manipulated fields:\n\n```json\n{\n  \"workspaceId\": \"11111111-2222-3333-4444-555555555555\",\n  \"createdDate\": \"1995-03-06T14:17:50.000Z\"\n}\n```\n\nThis confirms that client-controlled values are accepted and persisted by the server.\n\n### Impact\nThis vulnerability allows authenticated users to manipulate internal attributes of tool resources.\n\nConfirmed impacts include:\n\n- Cross-workspace reassignment of tools (workspaceId)\n- Unauthorized modification of metadata (createdDate, updatedDate)\n\nIn multi-tenant deployments, this may allow an attacker to move tools between workspaces without authorization, breaking tenant isolation boundaries.","published":"2026-06-08T15:25:59.588Z","modified":"2026-08-12T03:51:25.235852480Z","cvss":null,"epss":{"score":0.00195,"percentile":0.09557,"asOf":"2026-08-16"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"npm","name":"flowise","fixedVersion":"3.1.2"}],"fix":null,"references":[{"type":"WEB","url":"https://github.com/FlowiseAI/Flowise/releases/tag/flowise%403.1.2"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/42xxx/CVE-2026-42862.json"},{"type":"ADVISORY","url":"https://github.com/FlowiseAI/Flowise/security/advisories/GHSA-x5v6-pj28-cwwm"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-42862"},{"type":"PACKAGE","url":"https://github.com/FlowiseAI/Flowise"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:25.235852480Z"}}