VulnerabilityPublished 28 Oct 2026

CVE-2026-99171: Linux kernel · ntfs3: free the sbi after a grace period

Source GCVE Database

Authoritative record:CVE-2026-99171

Not known to be exploited · fixed in c8b1a4840467930e01f1a9374d991d7a8a2896c1 : patch Linux kernel soon.

Data as of 28 Oct 2026, 13:58 UTC

Severity

High

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

Patch: Available – fixed in c8b1a4840467930e01f1a9374d991d7a8a2896c1, c01b091b06412d3b1b53d8c2925f6de586c8a2fc, 7abecef26a9be8f9de70659a3092250461a52072

Exploitation evidence

Disclosed: evidence found.
CVE published 28 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: 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 26 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.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, 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.

ghsa-2rj4-34vw-q254

What to do

Upgrade Linux kernel to c8b1a4840467930e01f1a9374d991d7a8a2896c1, c01b091b06412d3b1b53d8c2925f6de586c8a2fc or 7abecef26a9be8f9de70659a3092250461a52072.

Affected software

Product	Affected	Fixed in
LinuxLinux	Affected ≥ a3a956c78efaa202b1d75190136671cf6e87bfbe, < c8b1a4840467930e01f1a9374d991d7a8a2896c1	Fixed in c8b1a4840467930e01f1a9374d991d7a8a2896c1
LinuxLinux	Affected ≥ a3a956c78efaa202b1d75190136671cf6e87bfbe, < c01b091b06412d3b1b53d8c2925f6de586c8a2fc	Fixed in c01b091b06412d3b1b53d8c2925f6de586c8a2fc
LinuxLinux	Affected ≥ a3a956c78efaa202b1d75190136671cf6e87bfbe, < 7abecef26a9be8f9de70659a3092250461a52072	Fixed in 7abecef26a9be8f9de70659a3092250461a52072
LinuxLinux	Affected =6.2	Fixed in–

AI-suggested

A fix has been implemented that defers freeing the ntfs3 superblock private information using an RCU callback, ensuring it is not freed while still in use. The locking mechanism was also adjusted to prevent deadlocks. Users should update to the fixed Linux kernel version once available. Until then, the existing grace period in namespace_unlock() partially mitigates the issue during unmount operations.

Description

A use-after-free vulnerability exists in the Linux kernel's ntfs3 filesystem driver when using the 'nocase' mount option. The issue arises because the filesystem's private superblock information is freed without an RCU delay while lookups may still be accessing it, leading to a potential kernel memory corruption. The flaw is mitigated by a grace period in namespace_unlock() during unmount, but the fix involves deferring the freeing of this information via an RCU callback to prevent use-after-free conditions.

References

Community reviews

Loading reviews…