CVE-2026-89612: Linux kernel · ntfs: reject invalid MFT LCNs from boot sector
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 9.8 Critical.
Data as of 12 Nov 2026, 20:25 UTC
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 11 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 12 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 24.04 LTSlinux-aws-6.14pkg:deb/ubuntu/linux-aws-6.14?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlinux-aws-6.17pkg:deb/ubuntu/linux-aws-6.17?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlinux-azure-6.11pkg:deb/ubuntu/linux-azure-6.11?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlinux-azure-6.14pkg:deb/ubuntu/linux-azure-6.14?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlinux-azure-6.17pkg:deb/ubuntu/linux-azure-6.17?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlinux-azure-fde-6.14pkg:deb/ubuntu/linux-azure-fde-6.14?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A fix for this vulnerability is available in the specified Linux kernel versions. Users should update their Linux kernel to a patched version that resolves this issue. Since this is a kernel-level vulnerability, applying the official kernel updates from the vendor or distribution is the recommended remediation.
Description
A critical vulnerability in the Linux kernel's NTFS driver allows crafted NTFS boot sectors with invalid Master File Table (MFT) Logical Cluster Numbers (LCNs) to bypass validation checks. This occurs because the NTFS boot sector stores MFT locations as unsigned 64-bit values, but the kernel code incorrectly decodes them as signed 64-bit integers, enabling negative values to pass bounds checks. This flaw can lead to out-of-bounds memory access in the MFT zone allocator.
References
- ubuntu.com/security/CVE-2026-89612 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-89612 (opens in a new tab)
- git.kernel.org/linus/cc9d09fef78410bcd37ac05168cbd5f6dd75d3d2 (opens in a new tab)
- git.kernel.org/stable/c/8f8420b68a6f05ca2b03779d8208814ec539b9e5 (opens in a new tab)
- git.kernel.org/stable/c/cc9d09fef78410bcd37ac05168cbd5f6dd75d3d2 (opens in a new tab)