CVE-2026-56857
Last modified
CVE-2026-56857 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. 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).. EPSS estimates a 0.21% chance of exploitation in the next 30 days.
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).
Metrics
Weakness Enumeration
Affected Software
Source: CNA advisory (CVE.org). NVD analysis pending.
| Vendor | Product | Versions |
|---|---|---|
| Go standard library | os | < 1.26.9; >= 1.27.0-0, < 1.27.2 |
| Go standard library | internal/syscall/windows | < 1.26.9; >= 1.27.0-0, < 1.27.2 |
References
Timeline
- Published
- Last Modified
- Status
- Awaiting Analysis
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How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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