CVE-2025-23143Public exploit

Kernel crash via stale LOCKDEP lock class

Published May 1, 2025 · Updated Sep 8, 2026

NULL pointer dereference in Linux kernel networking before branch-specific fixes allows local users to crash LOCKDEP-enabled systems. The socket lock-class metadata can outlive the unloaded CIFS or NFS module; hlock_class() then returns NULL and check_wait_context() dereferences it. Triggering requires LOCKDEP plus privileges to mount CIFS, alter firewall rules, unmount, and unload the module; the bounded result is a kernel crash.

CVSS severity5.5
Medium
EPSS probability0.21%
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 Linux kernel networking before branch-specific fixes allows local users to crash LOCKDEP-enabled systems. The socket lock-class metadata can outlive the unloaded CIFS or NFS module; hlock_class() then returns NULL and check_wait_context() dereferences it. Triggering requires LOCKDEP plus privileges to mount CIFS, alter firewall rules, unmount, and unload the module; the bounded result is a kernel crash.

The record

CVE
CVE-2025-23143
Published
May 1, 2025
Updated
Sep 8, 2026
Vendor
Siemens
Product
SIPLUS S7-1500 CPU 1518-4 PN/DP MFP
Classifications
CWE-476, T1499.004
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. May 1, 2025CVE publishedPublication date reported by the CVE source.
  2. Sep 8, 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=V3.1.6 <*

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Siemens · SIPLUS S7-1500 CPU 1518-4 PN/DP MFPversion=V3.1.6 <*
The Linux Kernel Organization · Linuxversion=2.6.20; version=ed07536ed6731775219c1df7fa26a7588753e693 <0bb2f7a1ad1f11d861f58e5ee5051c8974ff9569; version=ed07536ed6731775219c1df7fa26a7588753e693 <2155802d3313d7b8365935c6b8d6edc0ddd7eb94; version=ed07536ed6731775219c1df7fa26a7588753e693 <5f7f6abd92b6c8dc8f19625ef93c3a18549ede04; version=ed07536ed6731775219c1df7fa26a7588753e693 <83083c5fc7cf9b0f136a42f26aba60da380f3601; version=ed07536ed6731775219c1df7fa26a7588753e693 <905d43b8ad2436c240f844acb3ebcc7a99b8ebf1; version=ed07536ed6731775219c1df7fa26a7588753e693 <b7489b753667bc9245958a4896c9419743083c27; version=ed07536ed6731775219c1df7fa26a7588753e693 <c11247a21aab4b50a23c8b696727d7483de2f1e1; version=ed07536ed6731775219c1df7fa26a7588753e693 <d51e47e2ab6ef10a317d576075cf625cdbf96426; version=ed07536ed6731775219c1df7fa26a7588753e693 <feda73ad44a5cc80f6bf796bb1099a3fe71576d4
Siemens · SIMATIC S7-1500 CPU 1518F-4 PN/DP MFPversion=V3.1.6 <*
Siemens · SIMATIC CN 4100version=0 <V5.0
Siemens · SIMATIC S7-1500 CPU 1518-4 PN/DP MFPversion=V3.1.6 <*

Published CVSS scores

5.5Siemens ProductCERTCVSS: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 exploitPublished

Weakness, pattern, technique

CWE-476NULL Pointer Dereference
T1499.004Application or System Exploitation

Public exploit references

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