CVE-2026-90164

Kernel crash via unchecked proc initialization failure

Published Sep 17, 2026 · Updated Sep 17, 2026

NULL dereference in Linux ksmbd 7.0 allows local users to crash the kernel via server startup after proc initialization fails. ksmbd_server_init() continues after ksmbd_proc_init() discards partially allocated state, so startup reaches percpu_counter_set() with a NULL per-CPU pointer. The crash path requires an SMP system, a procfs or counter allocation failure, and privileged local server startup rather than an ordinary remote SMB request.

CVSS severity4.1
Medium
EPSS probability0.20%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

NULL dereference in Linux ksmbd 7.0 allows local users to crash the kernel via server startup after proc initialization fails. ksmbd_server_init() continues after ksmbd_proc_init() discards partially allocated state, so startup reaches percpu_counter_set() with a NULL per-CPU pointer. The crash path requires an SMP system, a procfs or counter allocation failure, and privileged local server startup rather than an ordinary remote SMB request.

The record

CVE
CVE-2026-90164
Published
Sep 17, 2026
Updated
Sep 17, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
Unavailable
Attack vector
local
Privileges
admin

Timeline

How it unfolded

  1. Sep 17, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 17, 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=7.0
  2. Affected versionversion=b38f99c1217ae04753340f0fdcd8f35bf56841dc <db97f3763727d652112ae70038d4e17b3ce277bb
  3. Affected versionversion=b38f99c1217ae04753340f0fdcd8f35bf56841dc <fb4ba2bdfc1de8866e7c8e00df99f4b03ff42f09

What conditions does exploitation require?

Attack vectorlocal
Required privilegesadmin

What is affected?

The Linux Kernel Organization · Linuxversion=7.0; version=b38f99c1217ae04753340f0fdcd8f35bf56841dc <db97f3763727d652112ae70038d4e17b3ce277bb; version=b38f99c1217ae04753340f0fdcd8f35bf56841dc <fb4ba2bdfc1de8866e7c8e00df99f4b03ff42f09

Published CVSS scores

7.2TenableAV:L/AC:L/Au:N/C:C/I:C/A:C
4.1Amazon LinuxCVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H
4.1SUSECVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H
5.5TenableCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
5.5TenableCVSS:3.0/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.

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
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

No sourced classifications are available.

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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