CVE-2026-42862: Flowise Remote Code Execution Vulnerability

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-x5v6-pj28-cwwm",
  "modified" : "2026-06-09T13:09:57Z",
  "published" : "2026-05-14T14:52:40Z",
  "aliases" : [ "CVE-2026-42862" ],
  "summary" : "FlowiseAI has Mass Assignment in Tool Update Endpoint that 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.",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "npm",
      "name" : "flowise"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "3.1.2"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 3.1.1"
    }
  } ],
  "references" : [ {
    "type" : "WEB",
    "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"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/FlowiseAI/Flowise/releases/tag/flowise%403.1.2"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-284", "CWE-639", "CWE-915" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-05-14T14:52:40Z",
    "nvd_published_at" : "2026-06-08T16:16:39Z"
  }
}