CVE-2026-99175

Local crash via fsnotify connector teardown race

Published Oct 28, 2026 · Updated Oct 28, 2026

A race in Linux kernel fsnotify allows local users to trigger a kernel fault via an fdinfo read concurrent with connector teardown. fsnotify_destroy_marks() permits replacement marks to be inserted behind its traversal cursor, leaving a surviving watch attached to a detached connector and causing igrab(NULL). Exploitation requires winning the unprivileged read race; the resulting fault interrupts execution, with system panic or reboot depending on kernel settings.

CVSS severityUnavailable
Unscored
EPSS probability0.18%
Next 30 days · Nov 1, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

A race in Linux kernel fsnotify allows local users to trigger a kernel fault via an fdinfo read concurrent with connector teardown. fsnotify_destroy_marks() permits replacement marks to be inserted behind its traversal cursor, leaving a surviving watch attached to a detached connector and causing igrab(NULL). Exploitation requires winning the unprivileged read race; the resulting fault interrupts execution, with system panic or reboot depending on kernel settings.

The record

CVE
CVE-2026-99175
Published
Oct 28, 2026
Updated
Oct 28, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
T1499.004
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Oct 28, 2026CVE publishedPublication date reported by the CVE source.
  2. Oct 28, 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=4.12
  2. Affected versionversion=6b3f05d24d355f50f3d9814304650fcab0efb482 <36ebddca56b9d8993d6dc984fdecc748ee1f5e06
  3. Affected versionversion=6b3f05d24d355f50f3d9814304650fcab0efb482 <472589eacdf10b5f9bd10b333957ed5291b2544b
  4. Affected versionversion=6b3f05d24d355f50f3d9814304650fcab0efb482 <952501bfc6e5e654ac4a17ec9d90c1ec614bd9f1

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=4.12; version=6b3f05d24d355f50f3d9814304650fcab0efb482 <36ebddca56b9d8993d6dc984fdecc748ee1f5e06; version=6b3f05d24d355f50f3d9814304650fcab0efb482 <472589eacdf10b5f9bd10b333957ed5291b2544b; version=6b3f05d24d355f50f3d9814304650fcab0efb482 <952501bfc6e5e654ac4a17ec9d90c1ec614bd9f1

Published CVSS scores

No CVSS assessment is available in this record.

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Activity data is delayed. The latest report is Sep 28, 2026.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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