CVE-2026-70027: Windows Subsystem for Linux heap buffer overflow privilege escalation

CVE-2026-70027 · Severity: high · CVSS 7.8 · Published 2026-10-13

Windows Subsystem for Linux (WSL) contains a heap buffer overflow vulnerability that allows an authorized local user to escalate their privileges to a higher level of access. An attacker with legitimate login credentials could exploit this flaw to gain elevated system permissions and take control of the affected system.

Technologies: Microsoft Windows Subsystem For Linux. Vendors: Microsoft.

Quick answers

Is CVE-2026-70027 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-70027 being exploited in the wild.
How severe is CVE-2026-70027?
High severity, with a CVSS score of 7.8, published 13 October 2026.
Which products and versions are affected?
Microsoft Windows Subsystem for Linux.
Is there a fix for CVE-2026-70027?
No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-70027 attacked?
It is attacked with local access, in an operating system.
Am I affected by CVE-2026-70027?
Check whether you run Microsoft Windows Subsystem For Linux. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A heap-based buffer overflow exists in Windows Subsystem for Linux that can be triggered by an authenticated local attacker. The vulnerability permits privilege escalation from a standard user context to a higher privilege level. This is a memory corruption issue requiring local access with valid credentials; no fix information is publicly available yet.

Affected products

  • Microsoft Windows Subsystem for Linux

Timeline

  • 2026-10-13: disclosed

References

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