CVE-2026-64359

Filesystem operation hangs via unchecked segment numbers

Published Jul 25, 2026 · Updated Jul 25, 2026

Denial of service in Linux kernel NILFS2 allows local users to hang concurrent filesystem operations via crafted CLEAN_SEGMENTS requests. nilfs_clean_segments() accepts out-of-range user segment numbers, and nilfs_sufile_updatev() logs each warning while holding ns_segctor_sem and sufile mi_sem. Administrative access to a mounted NILFS2 filesystem is required; repeated calls across mounts can saturate printk and stall chmod and other operations.

CVSS severity4.4
Medium
EPSS probability0.12%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Denial of service in Linux kernel NILFS2 allows local users to hang concurrent filesystem operations via crafted CLEAN_SEGMENTS requests. nilfs_clean_segments() accepts out-of-range user segment numbers, and nilfs_sufile_updatev() logs each warning while holding ns_segctor_sem and sufile mi_sem. Administrative access to a mounted NILFS2 filesystem is required; repeated calls across mounts can saturate printk and stall chmod and other operations.

The record

CVE
CVE-2026-64359
Published
Jul 25, 2026
Updated
Jul 25, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
T1499
Attack vector
local
Privileges
admin

Timeline

How it unfolded

  1. Jul 25, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 25, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=071cb4b81987a28c7ac2702003cff3e61684a630 <0789f0a6710713254a08f3a7d2ecbb6d1cbcf0aa
  2. Affected versionversion=071cb4b81987a28c7ac2702003cff3e61684a630 <0e7a690fe435f8d5ea3feb7c1d8d73ba7e8b8aa9
  3. Affected versionversion=071cb4b81987a28c7ac2702003cff3e61684a630 <223463c488b0554212a94de971ea538eb2805fc7
  4. Affected versionversion=071cb4b81987a28c7ac2702003cff3e61684a630 <286f77d002a337735c0846d7480a82d9cda2aa31
  5. Affected versionversion=071cb4b81987a28c7ac2702003cff3e61684a630 <39607452b1400c7bf748f15122df4d058b768c5b
  6. Affected versionversion=071cb4b81987a28c7ac2702003cff3e61684a630 <3ed388ec3b8922383d1e2d4432d7bd4cbbf8364e
  7. Affected versionversion=071cb4b81987a28c7ac2702003cff3e61684a630 <876c98e0fc65f071680c03c2e2ee3ef7ff9ca078
  8. Affected versionversion=071cb4b81987a28c7ac2702003cff3e61684a630 <d26aef771b4f6923da9f89d6d5b70d8def5853de
  9. Affected versionversion=2.6.31

What conditions does exploitation require?

Attack vectorlocal
Required privilegesadmin

What is affected?

The Linux Kernel Organization · Linux Kernelversion=071cb4b81987a28c7ac2702003cff3e61684a630 <0789f0a6710713254a08f3a7d2ecbb6d1cbcf0aa; version=071cb4b81987a28c7ac2702003cff3e61684a630 <0e7a690fe435f8d5ea3feb7c1d8d73ba7e8b8aa9; version=071cb4b81987a28c7ac2702003cff3e61684a630 <223463c488b0554212a94de971ea538eb2805fc7; version=071cb4b81987a28c7ac2702003cff3e61684a630 <286f77d002a337735c0846d7480a82d9cda2aa31; version=071cb4b81987a28c7ac2702003cff3e61684a630 <39607452b1400c7bf748f15122df4d058b768c5b; version=071cb4b81987a28c7ac2702003cff3e61684a630 <3ed388ec3b8922383d1e2d4432d7bd4cbbf8364e; version=071cb4b81987a28c7ac2702003cff3e61684a630 <876c98e0fc65f071680c03c2e2ee3ef7ff9ca078; version=071cb4b81987a28c7ac2702003cff3e61684a630 <d26aef771b4f6923da9f89d6d5b70d8def5853de; version=2.6.31

Published CVSS scores

4.4Amazon LinuxCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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