Description
Time-of-check time-of-use (toctou) race condition in Linux Kernel allows an authorized attacker to elevate privileges locally.
Published: 2026-10-13
Score: 7 High
EPSS: < 1% Very Low
KEV: No
Impact: Local Privilege Escalation
Action: Patch Promptly
AI Analysis

Impact

The vulnerability is a time‑of‑check time‑of‑use race condition in the Linux kernel that allows an attacker with local access to elevate their privileges. The flaw does not enable remote code execution, denial of service, or other remote attacks; its impact is strictly confined to gaining higher authority on the affected system. The concurrency error is a classic example of CWE‑367, where the kernel fails to guard a critical window between checking a condition and using its result.

Affected Systems

The flaw affects Microsoft Linux 3P (Third Party) distributions and the Microsoft Linux kernel MANA Network Driver. No specific version ranges are listed in the CNA data, so all installations of these products could potentially be vulnerable until a patch is applied.

Risk and Exploitability

The CVSS score of 7 categorizes the vulnerability as High severity. The EPSS score is <1 %, indicating a very low likelihood of abuse at the time of analysis. The flaw is not present in the CISA KEV catalog. Exploitation requires a local, authenticated user or process that can trigger the race on a kernel component; the narrow timing window makes it difficult to weaponize, yet it remains a significant risk for any local user or service with sufficient privileges.

Generated by OpenCVE AI on October 16, 2026 at 03:22 UTC.

Remediation

No solution or workaround provided in the CVE record.

OpenCVE Recommended Actions

  • Apply the latest Microsoft Linux kernel update that fixes CVE‑2026‑62840.
  • Restrict local user permissions by disabling root login for non‑essential accounts, removing unused SUID binaries, and configuring kernel lockdown to limit module loading by ordinary users.
  • Enable and monitor kernel audit logs for suspicious module load events or repeated attempts to manipulate kernel state, and implement automated alerts for any race‑condition–related activity.

Generated by OpenCVE AI on October 16, 2026 at 03:22 UTC.

Tracking

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Advisories

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History

Fri, 16 Oct 2026 13:45:00 +0000

Type Values Removed Values Added
CPEs cpe:2.3:a:microsoft:linux_kernel_mana_network_driver:*:*:*:*:*:*:*:*
Vendors & Products Microsoft linux Kernel Mana Network Driver

Wed, 14 Oct 2026 00:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Tue, 13 Oct 2026 21:00:00 +0000

Type Values Removed Values Added
Description Time-of-check time-of-use (toctou) race condition in Linux Kernel allows an authorized attacker to elevate privileges locally.
Title Linux Kernel Elevation of Privilege Vulnerability
First Time appeared Microsoft
Microsoft linux 3p \(third Party\) Distros
Microsoft linux Kernel Mana Network Driver
Weaknesses CWE-367
CPEs cpe:2.3:a:microsoft:linux_3p_\(third_party\)_distros:*:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:linux_kernel_mana_network_driver:*:*:*:*:*:*:*:*
Vendors & Products Microsoft
Microsoft linux 3p \(third Party\) Distros
Microsoft linux Kernel Mana Network Driver
References
Metrics cvssV3_1

{'score': 7, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C'}


Subscriptions

Microsoft Linux 3p \(third Party\) Distros
cve-icon MITRE

Status: PUBLISHED

Assigner: microsoft

Published:

Updated: 2026-10-31T18:09:43.054Z

Reserved: 2026-07-14T21:10:38.083Z

Link: CVE-2026-62840

cve-icon Vulnrichment

Updated: 2026-10-13T21:10:35.311Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-10-13T21:17:40.033

Modified: 2026-10-16T14:17:25.377

Link: CVE-2026-62840

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-10-17T17:45:11Z

Weaknesses
  • CWE-367

    Time-of-check Time-of-use (TOCTOU) Race Condition