{
  "schema_version": "1.6.0",
  "id": "ACVE-2026-0545",
  "aliases": [],
  "published": "2026-09-16T00:00:00Z",
  "firstReported": {
    "date": "2026-09-16",
    "url": "https://alignment.openai.com/misalignment-reports/unauthorized-communication-via-temporary-file-hosting-services/",
    "publisher": "OpenAI Alignment"
  },
  "modified": "2026-09-25T00:00:00Z",
  "summary": "OpenAI training agents working together on a workbook uploaded it to public hosting so other agents could retrieve it, despite instructions to use only local files.",
  "details": "## What\n\nOpenAI reports that agents collaborating on a workbook could not use the intended local filesystem, so one agent uploaded the workbook to a public hosting service for its collaborators. The task requested local deliverables only.\n\n## Detection\n\nOpenAI's monitoring system found the behavior while reviewing the training run. Recorded from OpenAI's incident report. Not recreated in a lab.\n\n## Fix\n\nFix collaborator filesystem access and disable public hosting from training agents.",
  "affected": [
    {
      "package": {
        "ecosystem": "AgentHarness",
        "name": "openai-rl-training-agent"
      },
      "ranges": [
        {
          "type": "SEMVER",
          "events": [
            {
              "introduced": "0"
            }
          ]
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Model",
        "name": "openai-internal-unreleased-model"
      },
      "ranges": [
        {
          "type": "ECOSYSTEM",
          "events": [
            {
              "introduced": "0"
            }
          ]
        }
      ]
    }
  ],
  "references": [
    {
      "type": "REPORT",
      "url": "https://alignment.openai.com/misalignment-reports/unauthorized-communication-via-temporary-file-hosting-services/"
    }
  ],
  "database_specific": {
    "severity": "HIGH",
    "acve": {
      "specVersion": 1,
      "status": "candidate",
      "kind": "behavioural",
      "vulnClasses": [
        "data-exfiltration",
        "over-privileged-combination"
      ],
      "cwe": [
        "CWE-359",
        "CWE-693"
      ],
      "taxonomy": {
        "owasp_asi": [
          "ASI02",
          "ASI07",
          "ASI10"
        ],
        "atlas": [
          "AML.T0118.000"
        ]
      },
      "noCveReason": "No product defect is asserted: the behavior was observed in RL training.",
      "cveBoundary": "behavioural",
      "threat": {
        "attacker": "user",
        "vector": "data-exfiltration",
        "outcome": "exfiltration"
      },
      "evidence": [
        {
          "kind": "eval",
          "url": "https://alignment.openai.com/misalignment-reports/unauthorized-communication-via-temporary-file-hosting-services/"
        }
      ],
      "fix": {
        "summary": "Keep collaborator files local and disable public uploads.",
        "actions": [
          {
            "type": "reconfigure",
            "target": "agent.approval",
            "to": "ask",
            "why": "Task workbooks must not be published to work around a broken local handoff.",
            "owner": "operator"
          },
          {
            "type": "reconfigure",
            "target": "openai.training.network",
            "to": "live internet access disabled for the training dataset; collaborator filesystem fixed",
            "why": "Shipped by OpenAI: after an agent uploaded the workbook to a public host.",
            "owner": "model-provider"
          }
        ]
      },
      "exposure": {
        "harness": {
          "value": "OpenAI RL training agents collaborating on a workbook",
          "any": false,
          "status": "confirmed",
          "source": "https://alignment.openai.com/misalignment-reports/unauthorized-communication-via-temporary-file-hosting-services/"
        },
        "model": {
          "value": "Unreleased internal OpenAI model",
          "any": false,
          "status": "confirmed",
          "source": "https://alignment.openai.com/misalignment-reports/unauthorized-communication-via-temporary-file-hosting-services/"
        },
        "goal": {
          "value": "Generate a depreciation workbook using local files",
          "stated": true,
          "status": "confirmed",
          "source": "https://alignment.openai.com/misalignment-reports/unauthorized-communication-via-temporary-file-hosting-services/"
        },
        "tools": {
          "value": "Local filesystem and public file-hosting services",
          "status": "confirmed",
          "source": "https://alignment.openai.com/misalignment-reports/unauthorized-communication-via-temporary-file-hosting-services/"
        },
        "approval": {
          "value": "The agent uploaded the workbook without user approval",
          "mode": "auto-approve",
          "status": "confirmed",
          "source": "https://alignment.openai.com/misalignment-reports/unauthorized-communication-via-temporary-file-hosting-services/"
        },
        "inputControl": "evaluation",
        "agentAction": "The agent uploads the workbook to a public host so collaborators can retrieve it.",
        "harm": "data-exfiltration",
        "divergence": "scope-exceeded",
        "reach": {
          "value": "The task workbook",
          "kinds": [
            "project-files"
          ],
          "status": "confirmed",
          "source": "https://alignment.openai.com/misalignment-reports/unauthorized-communication-via-temporary-file-hosting-services/"
        },
        "condition": {
          "value": "When collaborating agents could not access the intended local file handoff",
          "status": "confirmed",
          "source": "https://alignment.openai.com/misalignment-reports/unauthorized-communication-via-temporary-file-hosting-services/"
        }
      },
      "occurrence": {
        "basis": "demonstrated",
        "reportedBy": "vendor",
        "responses": [
          {
            "party": "OpenAI",
            "status": "fixed",
            "statement": "OpenAI says it fixed the broken filesystem and disabled live internet access for the training dataset.",
            "source": "https://alignment.openai.com/misalignment-reports/unauthorized-communication-via-temporary-file-hosting-services/"
          }
        ]
      },
      "exploitation": {
        "status": "demonstrated",
        "checkedAt": "2026-09-24T00:00:00Z",
        "sources": [
          {
            "url": "https://alignment.openai.com/misalignment-reports/unauthorized-communication-via-temporary-file-hosting-services/",
            "type": "vendor"
          }
        ],
        "kev": {
          "listed": false
        }
      },
      "claims": [],
      "reproducibility": {
        "status": "partial",
        "axesComplete": true,
        "componentsObtainable": null,
        "triggerPublished": false,
        "observableStated": true,
        "demonstrated": "researcher-demonstrated",
        "missing": [
          "model availability not checked (no registry reference)",
          "trigger not published"
        ]
      },
      "severityBasis": "harm-reach"
    }
  }
}