{"id":"GHSA-6qr9-g2xw-cw92","aliases":["GO-2026-4527"],"url":"https://o3.security/vulnerability/GHSA-6qr9-g2xw-cw92","summary":"Dagu affected by unauthenticated RCE via inline DAG spec in default configuration","details":"### Summary\nDagu's default configuration ships with authentication disabled. The `POST /api/v2/dag-runs` endpoint accepts an inline YAML spec and executes its shell commands immediately with no credentials required — any dagu instance reachable over the network is fully compromised by default.\n\n### Details\n`internal/service/app/config/loader.go:226` sets `AuthModeNone` as the default. With no auth mode configured, `internal/frontend/api/v2/handlers/api.go:520` returns `nil` from `requireExecute()` — all permission checks pass without a valid session.\n\nThe `POST /api/v2/dag-runs` endpoint accepts a `spec` field containing a full YAML DAG definition. The spec is parsed and the commands execute immediately on the host with no validation beyond YAML parsing.\n\n### PoC\n```bash\ncurl -s -X POST http://TARGET:8080/api/v2/dag-runs \\\n  -H \"Content-Type: application/json\" \\\n  -d '{\"name\":\"poc\",\"spec\":\"steps:\\n  - name: rce\\n    command: id > /tmp/pwned\\n\"}'\n# Response: {\"dagRunId\":\"<uuid>\"}\n# /tmp/pwned contains: uid=1000(dagu) gid=1000(dagu)\n```\nConfirmed on `ghcr.io/dagu-org/dagu:latest` with no configuration changes.\n\n### Impact\nEvery dagu deployment using default settings — every Docker deployment, every install following the documentation, every instance without explicit `DAGU_AUTH_MODE` configuration — is fully compromised without credentials. An attacker with network access gets OS command execution as the dagu process user.","published":"2026-02-19T22:04:39Z","modified":"2026-02-23T19:26:21.632734Z","cvss":{"score":9.8,"severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Go","name":"github.com/dagu-org/dagu","fixedVersion":null}],"fix":null,"references":[{"type":"WEB","url":"https://github.com/dagu-org/dagu/security/advisories/GHSA-6qr9-g2xw-cw92"},{"type":"PACKAGE","url":"https://github.com/dagu-org/dagu"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-02-23T19:26:21.632734Z"}}