VulnerabilityPublished 17 Sep 2026Updated 30 Oct 2026

CVE-2026-90200: Linux kernel · fs/ntfs3: fix integer overflow in MFT cluster validation

Affects Linux kernelSource CVE Database V5

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Not known to be exploited · fixed in f77a8d9fdf58e298b36564a44c27fadc617bdd28 : update Linux kernel when convenient.

Data as of 30 Oct 2026, 12:51 UTC

Severity

Medium

Rated Medium by Threat Radar's AI analysis · CVSS not yet scored by NVD

Thin evidence

One scorer or none

Patch: Available – fixed in f77a8d9fdf58e298b36564a44c27fadc617bdd28, dc6d85de7e2656e56e10ff5ba514f2583a4f612b, c510c63873103a5da6a498fe537bdb5d6f8d03a2 +3

Exploitation evidence

Disclosed: evidence found.
CVE published 17 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 30 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponized: A Metasploit exploit module or Exploit-DB entry exists (Metasploit scanner modules do not count), or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade to a fixed release listed under Affected software.

Affected software

Product	Affected	Fixed in
LinuxLinux	Affected ≥ 82cae269cfa953032fbb8980a7d554d60fb00b17, < f77a8d9fdf58e298b36564a44c27fadc617bdd28	Fixed in f77a8d9fdf58e298b36564a44c27fadc617bdd28
LinuxLinux	Affected ≥ 82cae269cfa953032fbb8980a7d554d60fb00b17, < dc6d85de7e2656e56e10ff5ba514f2583a4f612b	Fixed in dc6d85de7e2656e56e10ff5ba514f2583a4f612b
LinuxLinux	Affected ≥ 82cae269cfa953032fbb8980a7d554d60fb00b17, < c510c63873103a5da6a498fe537bdb5d6f8d03a2	Fixed in c510c63873103a5da6a498fe537bdb5d6f8d03a2
LinuxLinux	Affected ≥ 82cae269cfa953032fbb8980a7d554d60fb00b17, < 169383d8914b8fe03464a83540b5b6de3e7831af	Fixed in 169383d8914b8fe03464a83540b5b6de3e7831af
LinuxLinux	Affected ≥ 82cae269cfa953032fbb8980a7d554d60fb00b17, < 805cc5554b13d045dce9b03c13eaf015418739fd	Fixed in 805cc5554b13d045dce9b03c13eaf015418739fd
LinuxLinux	Affected ≥ 82cae269cfa953032fbb8980a7d554d60fb00b17, < 8ecb1525a9520acd3d5ea3e2593e487fd9f143ce	Fixed in 8ecb1525a9520acd3d5ea3e2593e487fd9f143ce

AI-suggested

A patch is available and has been applied in multiple Linux kernel commits following version 5.15. Users and administrators should update to a fixed kernel version containing these commits to remediate the vulnerability. Since the issue is fixed in these versions, no additional mitigation steps are required.

Description

A vulnerability in the Linux kernel's NTFS3 filesystem driver allows an integer overflow during MFT cluster validation. This flaw occurs in the ntfs_init_from_boot() function where multiplication of large MFT cluster numbers with sectors per cluster can wrap around, bypassing validation checks. While this typically causes mount failures due to block layer read errors, the improper validation could potentially lead to accepting malformed records.

Impact

The integer overflow flaw can cause the NTFS3 driver to accept malformed MFT cluster numbers, potentially leading to improper mount behavior. In practice, this results in mount failures due to block layer read errors rather than more severe exploitation. There is no evidence of active exploitation in the wild. The impact is limited to denial of service (mount failure) rather than data corruption or privilege escalation.

Summary

CVE-2026-90200 addresses an integer overflow in the Linux kernel's NTFS3 driver during the validation of MFT cluster numbers read from the boot sector. The vulnerability arises because the multiplication of 64-bit MFT cluster numbers (mlcn, mlcn2) by sectors per cluster (sct_per_clst) can overflow and wrap, causing the validation check to be bypassed. Although the block layer currently prevents dangerous reads by failing mounts, the validation logic itself is incorrect. The fix uses check_mul_overflow() to detect multiplication overflow and reject invalid values early, preserving existing validation semantics without tightening checks unnecessarily. This issue affects Linux kernel version 5.15 and has been fixed in several subsequent commits.

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 30 Oct 2026, 12:51 UTC

Technical details

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