CVE-2023-0386
Linux Kernel · Operating systems
Linux Kernel Improper Ownership Management Vulnerability
At a glance
Exploited. Added to CISA’s catalog of exploited vulnerabilities on June 17, 2025.
Affected product: Linux Kernel (category Operating systems, indicative classification). Name in CISA’s catalog: Linux Kernel.
What should I do?
Apply the patches or mitigations from Linux; if none are available, stop using the product. For cloud services, follow the guidance from Linux.
Deadline set by CISA for US federal agencies: 21 days (due July 8, 2025). It only binds those agencies, but it is a useful measure of urgency.
- Linux security advisories page (general page, not the advisory for this vulnerability)
- The vendor’s specific advisory is listed in the NVD references: CVE-2023-0386 on the NVD website.
Original text of the required action (CISA)
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Timeline
- Vulnerability published Publication date (NVD)
- Exploitation confirmed Added to CISA’s KEV catalog
- CISA deadline Remediation deadline set for US federal agencies
The facts, with their sources
- Exploitation confirmed
- Yes, on June 17, 2025 Date added to the catalog of exploited vulnerabilities. Exploitation itself may have started earlier. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
- Ransomware
- No known use to date That does not guarantee it is not being used: the information is not public. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
- Hunt for compromise
- Not requested by CISA Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
- CISA required action
- Apply the patches or mitigations from Linux; if none are available, stop using the product. For cloud services, follow the guidance from Linux. Rewritten by this site from CISA’s original text. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
- CISA deadline
- July 8, 2025, 21 days Set for US federal agencies: a measure of urgency, not an obligation elsewhere. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
- Vulnerability published
- March 22, 2023 Source: National Vulnerability Database (NVD), collected September 29, 2026 at 15:00 UTC
- Product according to CISA
- Linux Kernel Filed by this site under “Operating systems” (indicative classification). Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
- CVSS vector
- CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Technical detail of the score: attack vector, complexity, impact. Source: National Vulnerability Database (NVD), collected September 29, 2026 at 15:00 UTC
Severity and activity
FIRST’s EPSS model. Since exploitation is already confirmed, this figure is mostly useful to compare activity. Collected Sep 29, 2026.
Description
A flaw was found in the Linux kernel, where unauthorized access to the execution of the setuid file with capabilities was found in the Linux kernel’s OverlayFS subsystem in how a user copies a capable file from a nosuid mount into another mount. This uid mapping bug allows a local user to escalate their privileges on the system.
Official description from the NVD, collected Sep 29, 2026. CVE® description © The MITRE Corporation.
Linux Kernel contains an improper ownership management vulnerability, where unauthorized access to the execution of the setuid file with capabilities was found in the Linux kernel’s OverlayFS subsystem in how a user copies a capable file from a nosuid mount into another mount. This uid mapping bug allows a local user to escalate their privileges on the system.
Summary from CISA (KEV catalog).
CERT-FR advisories
No advisory among the latest CERT-FR publications this site follows. That does not mean there are none.
Information reused under the Open Licence 2.0 (Etalab); the date of last update is shown for each advisory. This site is neither affiliated with nor endorsed by ANSSI.
Sources for this page
- CISA KEV catalog: exploitation, date added, required action, deadline, ransomware.
- NVD (NIST): CVSS severity, publication date, description, vendor references.
- EPSS (FIRST): probability of exploitation.
- CERT-FR: advisories and alerts (in French).
- Brand and category: indicative classification by this site (method).