CVE-2026-64373 — cpufreq: Fix hotplug-suspend race during reboot
In the Linux kernel, the following vulnerability has been resolved: cpufreq: Fix hotplug-suspend race during reboot During system reboot, cpufreq_suspend() is called via the kernel_restart() -> device_shutdown() path. Unlike the normal system suspend path, the reboot path does not call freeze_processes(), so userspace processes and kernel threads remain active. This allows CPU hotplug operations to run concurrently with cpufreq_suspend(). The original code has no synchronization with CPU hotplug, leading to a race condition where governor_data can be freed by the hotplug path while cpufreq_suspend() is still accessing it, resulting in a null pointer dereference: Unable to handle kernel NULL pointer dereference Call Trace: do_kernel_fault+0x28/0x3c cpufreq_suspend+0xdc/0x160 device_shutdown+0x18/0x200 kernel_restart+0x40/0x80 arm64_sys_reboot+0x1b0/0x200 Fix this by adding cpus_read_lock()/cpus_read_unlock() to cpufreq_suspend() to block CPU hotplug operations while suspend is in progress. [ rjw: Changelog edits ]
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- Technical severity (medium)+3
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Linux Linux, Linux Linux Kernel).
- Apply the fixed version or the patch documented under Remediation.
- Search available logs for exploit probes matching the vulnerability class (logic error), errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Linux | Linux |
version 5f466713989250938624afa79dc33bae20920700≥ 65650b35133ff20f0c9ef0abd5c3c66dbce3ae57 and < 9103078c7b3091a2fbb52af176f95982ee7dd7f8≥ 65650b35133ff20f0c9ef0abd5c3c66dbce3ae57 and < cd4524ff6567fa4458a5bec4b017105e671d393e≥ 65650b35133ff20f0c9ef0abd5c3c66dbce3ae57 and < 73255d702c7560185fd5951aadcf7eb057c2f453≥ 65650b35133ff20f0c9ef0abd5c3c66dbce3ae57 and < a0ef2fc89d28ca62923376c4b8ffaa57136a36be≥ 65650b35133ff20f0c9ef0abd5c3c66dbce3ae57 and < 6e175c00c62dca3d91b987015808b5d52e8db2b4≥ 65650b35133ff20f0c9ef0abd5c3c66dbce3ae57 and < a0106b41f9a724868d390b8b3b4ea5ca0e04ea53≥ 65650b35133ff20f0c9ef0abd5c3c66dbce3ae57 and < a9029dd55696c651ee46912afa2a166fa456bb3e and 11 moreversion 8bfa06ea6e81bf08d2132d7e70c2b5313b34caf8version 7ccf3b8b7a12dc9da158c2e699c36d04b2496944≥ 65650b35133ff20f0c9ef0abd5c3c66dbce3ae57 and < 6d5dd354c37abaf4d60400c55c71f23ba2b33639version 89ab39da1452d272007acc5912d4008047b86706version cb4b4601f910c78d2b49f637a12ef98b41cb76a9≥ 4.4.198 and < 4.5≥ 4.9.198 and < 4.10≥ 4.14.151 and < 4.15≥ 4.19.81 and < 4.20≥ 5.3.8 and < 5.4version 5.4 |
Vulnerable | CVE Program (cve.org) e CISA ADP |
| Linux | Linux Kernel |
≥ 6.7 and < 6.12.96≥ 4.9.198 and < 4.10≥ 4.14.151 and < 4.15≥ 4.19.81 and < 4.20≥ 5.3.8 and < 5.4≥ 5.4.1 and < 5.10.261≥ 5.11 and < 5.15.212≥ 5.16 and < 6.1.178 and 10 more≥ 6.2 and < 6.6.145≥ 4.4.198 and < 4.5≥ 6.13 and < 6.18.39≥ 6.19 and < 7.1.4version 5.4version 5.4-rc4version 5.4-rc5version 5.4-rc6version 5.4-rc7version 5.4-rc8 |
Vulnerable | NIST National Vulnerability Database |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 4.7 | CVSS 3.1 | Medium | 1.0 | 3.6 | nvd@nist.gov via NIST National Vulnerability Database |
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H (score shown at the top: nvd@nist.gov) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Local/physical vector: focus on endpoint telemetry (EDR) from affected hosts.
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · linux/linux
- Record published
- Fix documented
- CVSS changed · 4.7
- Source status changed · → Analyzed
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 15, 2026 – Oct 15, 2026
References
8 on the record
- git.kernel.org/stable/c/6d5dd354c37abaf4d60400c55c71f23ba2b33639
- git.kernel.org/stable/c/9103078c7b3091a2fbb52af176f95982ee7dd7f8
- git.kernel.org/stable/c/6e175c00c62dca3d91b987015808b5d52e8db2b4
- git.kernel.org/stable/c/a0ef2fc89d28ca62923376c4b8ffaa57136a36be
- git.kernel.org/stable/c/a0106b41f9a724868d390b8b3b4ea5ca0e04ea53
- git.kernel.org/stable/c/cd4524ff6567fa4458a5bec4b017105e671d393e
- git.kernel.org/stable/c/73255d702c7560185fd5951aadcf7eb057c2f453
- git.kernel.org/stable/c/a9029dd55696c651ee46912afa2a166fa456bb3e
Elsewhere on this site
Related CVEs (same products)
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- Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 12h
- Unknown CVE-2026-98424 wifi: cfg80211: undo netns switch if renaming the wiphy fails 1d
- Unknown CVE-2026-98425 wifi: mac80211: don't warn when an IBSS has no channel to scan 1d
- Unknown CVE-2026-98426 wifi: mwifiex: fix IRQ leak using wrong index in MSI-X error path 1d
- Unknown CVE-2026-98427 net/sched: codel: bound the dropping loop per dequeue call 1d
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No FIRST EPSS score.
- No CISA SSVC assessment.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2026-64373 is "cpufreq: Fix hotplug-suspend race during reboot", rated Medium. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 4.7 describes technical severity. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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