# CVE-2023-0386: Linux Kernel privilege escalation in OverlayFS

Source: https://junglewise.ai/threats/cve-2023-0386-linux-kernel-privilege-escalation-in-overlayfs  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2025-06-17. Updated: 2026-05-15  
License: CC BY 4.0 with a link back

CVE-2023-0386 · Severity: critical · CVSS 7.8 · Exploited in the wild · Published 2025-06-17

A security vulnerability has been identified in the Linux kernel's OverlayFS component, which is commonly used for managing file systems in container environments and live operating systems. This flaw allows a person who already has limited access to a computer to gain full administrative (root) control. Such an escalation of privileges could allow an attacker to bypass security restrictions, access sensitive data, or disrupt system operations.

Technologies: [Linux Kernel](https://junglewise.ai/threats/technologies/kernel). Vendors: [Linux](https://junglewise.ai/threats/vendors/linux).

## Quick answers

**Is CVE-2023-0386 exploited in the wild?** Yes. CVE-2023-0386 is known to be exploited in the wild, first recorded on 17 June 2025. Treat it as urgent.

**How severe is CVE-2023-0386?** Critical severity, with a CVSS score of 7.8, published 17 June 2025.

**Which products and versions are affected?** Linux Linux Kernel OverlayFS subsystem; CanonicalHeader Ubuntu Linux 18.04 LTS, 20.04 LTS, 22.04 LTS; Debian Debian Linux 10.0.

**Is there a fix for CVE-2023-0386?** 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-2023-0386 attacked?** It is attacked with local access, in an operating system.

**Am I affected by CVE-2023-0386?** Check whether you run Linux Kernel. 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

An improper ownership management vulnerability (CWE-282) exists in the Linux kernel's OverlayFS subsystem. The flaw occurs during the process of copying a file with setuid capabilities from a 'nosuid' mount into another mount point. Due to a bug in UID mapping, the kernel fails to properly restrict the execution of these files, allowing a local, unprivileged attacker to execute a specially crafted file with elevated privileges. This effectively results in a local privilege escalation (LPE) to root. Patches have been released for major distributions including Debian and Ubuntu.

## Affected products

- Linux Linux Kernel OverlayFS subsystem
- CanonicalHeader Ubuntu Linux 18.04 LTS, 20.04 LTS, 22.04 LTS
- Debian Debian Linux 10.0

## Timeline

- 2023-06-01: advisory: Debian LTS security advisory published
- 2025-06-17: kev added: Added to CISA Known Exploited Vulnerabilities catalog
- 2025-06-17: disclosed: Public disclosure date listed in advisory

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