Dagu is a workflow engine with a built-in Web user interface. From version 2.0.0 to before version 2.3.1, the fix for CVE-2026-27598 added ValidateDAGName to CreateNewDAG and rewrote generateFilePath to use filepath.Base. This patched the CREATE path. The remaining API endpoints - GET, DELETE, RENAME, EXECUTE - all pass the {fileName} URL path parameter to locateDAG without calling ValidateDAGName. %2F-encoded forward slashes in the {fileName} segment traverse outside the DAGs directory. This issue has been patched in version 2.3.1.
https://github.com/dagu-org/dagu/security/advisories/GHSA-ph8x-4jfv-v9v8
https://github.com/dagu-org/dagu/commit/7d07fda8f9de3ae73dfb081ccd0639f8059c56bb