CVE-2026-56857

critical

Description

On Windows, when the target of Root.Mkdir or Root.MkdirAll is a junction pointing to an empty location, the operation can create a directory at the junction target even when that target is located outside the root. This only applies to operations where the last path component is a junction (path/to/junction, but not path/junction/target).

References

https://pkg.go.dev/vuln/GO-2026-6604

https://groups.google.com/g/golang-announce/c/U2fTuyDJznI

https://go.dev/issue/81739

https://go.dev/cl/847305

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-95420

Details

Source: Mitre, NVD

Published: 2026-10-08

Updated: 2026-10-09

Risk Information

CVSS v2

Base Score: 10

Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C

Severity: Critical

CVSS v3

Base Score: 9.8

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

Severity: Critical

EPSS

EPSS: 0.0021