CVE-2026-23189

Kernel crash via null filesystem-name comparison

Published Feb 14, 2026 · Updated Feb 14, 2026

NULL pointer dereference in affected Linux kernel CephFS clients allows local users to crash the kernel during authorization matching. ceph_mds_auth_match() passes a null mds_namespace filesystem name to strcmp() when an authorization rule contains an FS-name match. Exploitation requires a mounted CephFS kernel client whose mount omits mds_namespace and reaches that authorization rule; the bounded consequence is a kernel crash.

CVSS severity5.5
Medium
EPSS probability0.12%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

NULL pointer dereference in affected Linux kernel CephFS clients allows local users to crash the kernel during authorization matching. ceph_mds_auth_match() passes a null mds_namespace filesystem name to strcmp() when an authorization rule contains an FS-name match. Exploitation requires a mounted CephFS kernel client whose mount omits mds_namespace and reaches that authorization rule; the bounded consequence is a kernel crash.

The record

CVE
CVE-2026-23189
Published
Feb 14, 2026
Updated
Feb 14, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
CWE-476, T1499.004
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 14, 2026CVE publishedPublication date reported by the CVE source.
  2. Feb 14, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=07640d34a781bb2e39020a39137073c03c4aa932 <c6f8326f26bd20d648d9a55afd68148d1b6afe28
  2. Affected versionversion=22c73d52a6d05c5a2053385c0d6cd9984732799d <57b36ffc8881dd455d875f85c105901974af2130
  3. Affected versionversion=22c73d52a6d05c5a2053385c0d6cd9984732799d <7987cce375ac8ce98e170a77aa2399f2cf6eb99f
  4. Affected versionversion=6.18
  5. Affected versionversion=ca3da8b27ab9a0923ad477447cfb8fc7f4b4c523

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=07640d34a781bb2e39020a39137073c03c4aa932 <c6f8326f26bd20d648d9a55afd68148d1b6afe28; version=22c73d52a6d05c5a2053385c0d6cd9984732799d <57b36ffc8881dd455d875f85c105901974af2130; version=22c73d52a6d05c5a2053385c0d6cd9984732799d <7987cce375ac8ce98e170a77aa2399f2cf6eb99f; version=6.18; version=ca3da8b27ab9a0923ad477447cfb8fc7f4b4c523

Published CVSS scores

5.5Canonical UbuntuCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

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.

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

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-476NULL Pointer Dereference
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

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo