CVE-2026-31886
Prior to 2.2.4, the dagRunId request field accepted by the inline DAG execution endpoints is passed directly into filepath.Join to construct a temporary directory path without any format validation.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.43%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
Dagu is a workflow engine with a built-in Web user interface. Prior to 2.2.4, the dagRunId request field accepted by the inline DAG execution endpoints is passed directly into filepath.Join to construct a temporary directory path without any format validation. Go's filepath.Join resolves .. segments lexically, so a caller can supply a value such as ".." to redirect the computed directory outside the intended /tmp/<name>/<id> path. A deferred cleanup function that calls os.RemoveAll on that directory then runs unconditionally when the HTTP handler returns, deleting whatever directory the traversal resolved to. With dagRunId set to "..", the resolved directory is the system temporary directory (/tmp on Linux). On non-root deployments, os.RemoveAll("/tmp") removes all files in /tmp owned by the dagu process user, disrupting every concurrent dagu run that has live temp files. On root or Docker deployments, the call removes the entire contents of /tmp, causing a system-wide denial of service. This vulnerability is fixed in 2.2.4.
- CVSS 3.1
- 7.6 HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:H
- EPSS
- 0.43% probability · 37th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-22
- Affected
- dagu/dagu
- Source
- security-advisories@github.com
EPSS 0.4% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://github.com/dagu-org/dagu/commit/12c2e5395bd9331d49ca103593edfd0db39c4f38Patch
- https://github.com/dagu-org/dagu/security/advisories/GHSA-m4q3-457p-hh2xExploit, Mitigation, Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.