CVE-2026-31886: Dagu path traversal (CVSS 9.1)

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 breakdown

Attack vectorNetwork

Attack complexityLow

Privileges requiredLow

User interactionNone

ScopeChanged

ConfidentialityLow

IntegrityLow

AvailabilityHigh

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:H

Affected products

Dagu< 2.2.4

Remediation

Fixed in

Dagu≥ 2.2.4

Patch & vendor advisories

References

https://github.com/dagu-org/dagu/commit/12c2e5395bd9331d49ca103593edfd0db39c4f38Patch
https://github.com/dagu-org/dagu/security/advisories/GHSA-m4q3-457p-hh2xExploitMitigationVendor Advisory

Related CVEs

Recent high-severity vulnerabilities sharing a weakness type.

Frequently asked

Is CVE-2026-31886 being actively exploited?

CVE-2026-31886 is not in the CISA KEV catalog. A public exploit reference exists, so treat it as exploitable. Its EPSS exploit probability is 0.48%.

How severe is CVE-2026-31886?

CVE-2026-31886 has a CVSS 3.1 base score of 9.1, rated critical. EPSS estimates a 0.48% probability of exploitation.

Which products are affected by CVE-2026-31886?

Affected products include Dagu.

How do I fix CVE-2026-31886?

Upgrade affected software to a fixed version, for example Dagu 2.2.4 or later, then confirm no affected versions remain in your inventory.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2026-31886 against the real software inventory on every managed device, every day. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

See how prioritisation works Book a demo