CVE-2025-40346

System crash via NULL CPU clock dereference

Published Dec 16, 2025 · Updated Dec 16, 2025

NULL-pointer dereference in the Linux kernel allows local users to crash affected systems during CPU topology initialization. topology_parse_cpu_capacity() treats a NULL result from of_clk_get() as valid because PTR_ERR_OR_ZERO() returns zero for NULL, then passes it to clk_get_rate(). The path is reached during boot when a CPU device-tree node supplies capacity-dmips-mhz but its CPU clock lookup returns NULL, so the reported consequence is a system crash rather than data access or modification.

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 the Linux kernel allows local users to crash affected systems during CPU topology initialization. topology_parse_cpu_capacity() treats a NULL result from of_clk_get() as valid because PTR_ERR_OR_ZERO() returns zero for NULL, then passes it to clk_get_rate(). The path is reached during boot when a CPU device-tree node supplies capacity-dmips-mhz but its CPU clock lookup returns NULL, so the reported consequence is a system crash rather than data access or modification.

The record

CVE
CVE-2025-40346
Published
Dec 16, 2025
Updated
Dec 16, 2025
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
T1499.004
Attack vector
local
Privileges
Unavailable

Timeline

How it unfolded

  1. Dec 16, 2025CVE publishedPublication date reported by the CVE source.
  2. Dec 16, 2025Record 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=5.7
  2. Affected versionversion=b8fe128dad8f97cc9af7c55a264d1fc5ab677195 <02fbea0864fd4a863671f5d418129258d7159f68
  3. Affected versionversion=b8fe128dad8f97cc9af7c55a264d1fc5ab677195 <2eead19334516c8e9927c11b448fbe512b1f18a1
  4. Affected versionversion=b8fe128dad8f97cc9af7c55a264d1fc5ab677195 <3373f263bb647fcc3b5237cfaef757633b9ee25e
  5. Affected versionversion=b8fe128dad8f97cc9af7c55a264d1fc5ab677195 <3a01b2614e84361aa222f67bc628593987e5cdb2
  6. Affected versionversion=b8fe128dad8f97cc9af7c55a264d1fc5ab677195 <45379303124487db3a81219af7565d41f498167f
  7. Affected versionversion=b8fe128dad8f97cc9af7c55a264d1fc5ab677195 <64da320252e43456cc9ec3055ff567f168467b37
  8. Affected versionversion=b8fe128dad8f97cc9af7c55a264d1fc5ab677195 <a77f8434954cb1e9c42c3854e40855fdcf5ab235

What conditions does exploitation require?

Attack vectorlocal
Required privilegesUnavailable in this record.

What is affected?

The Linux Kernel Organization · Linuxversion=5.7; version=b8fe128dad8f97cc9af7c55a264d1fc5ab677195 <02fbea0864fd4a863671f5d418129258d7159f68; version=b8fe128dad8f97cc9af7c55a264d1fc5ab677195 <2eead19334516c8e9927c11b448fbe512b1f18a1; version=b8fe128dad8f97cc9af7c55a264d1fc5ab677195 <3373f263bb647fcc3b5237cfaef757633b9ee25e; version=b8fe128dad8f97cc9af7c55a264d1fc5ab677195 <3a01b2614e84361aa222f67bc628593987e5cdb2; version=b8fe128dad8f97cc9af7c55a264d1fc5ab677195 <45379303124487db3a81219af7565d41f498167f; version=b8fe128dad8f97cc9af7c55a264d1fc5ab677195 <64da320252e43456cc9ec3055ff567f168467b37; version=b8fe128dad8f97cc9af7c55a264d1fc5ab677195 <a77f8434954cb1e9c42c3854e40855fdcf5ab235

Published CVSS scores

5.5OracleCVSS: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
PrivilegesUnavailable
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

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