- Critical 9.8
CVE-2026-56857
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).
Scores
The facts
- Published
- 8 October 2026
- Last changed
- 9 October 2026
- NVD status
- Awaiting Analysis
- Severity
- Critical, CVSS 9.8 out of 10 (version 3.1)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- Known exploited
- Not in the CISA Known Exploited Vulnerabilities catalogue in this build.
- EPSS
- 0.5% chance of exploitation activity in the next 30 days (percentile 41).
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