[CVE-2026-97475][MODERATE REGULAR] thermal/drivers/tegra/soctherma: Switch to devm cooling device registration [ Upstream

[AL-KERNEL <alkernel@kernelcve.org>]

CVE: CVE-2026-97475
Priority: MODERATE REGULAR
AL-KERNEL base severity: MODERATE
KPANIC flag: NO
Patch: thermal/drivers/tegra/soctherma: Switch to devm cooling device registration [ Upstream
Commit: 6f2a863e7e9adf6088fe644259576181e60ee5e5
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=6f2a863e7e9adf6088fe644259576181e60ee5e5
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-97475
Analysis date: Thu, 24 Sep 2026 20:15:14 -0400
ActionableScore: 1
ActionableScore lower bound: unknown
Actionable bucket: Ordinary Moderate
Manual review required: NO

Summary:
No one-sentence report phrase was found.

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ABOUT THIS REPORT
======================================================================

The original Linux kernel CVE announcement for CVE-2026-97475 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-97475

The original announcement does not normally provide a security severity
estimate, CVSS assessment, or enough information to determine whether the
reported kernel bug represents a practically relevant security issue.

This report was generated by AL-KERNEL, an AI-assisted Linux kernel
vulnerability analysis system developed by Alexander Larkin. It combines
an autonomous classifier with LLM-assisted technical analysis and a
separate ActionableScore mechanism.

The purpose of this report is to prioritize Linux kernel CVEs before
manual review, identify cases that require prompt investigation, and
support automatic closure of issues that are unlikely to have meaningful
security impact.

Published priority for this report: MODERATE REGULAR
Manual review required: NO

A detailed explanation of the methodology and priority rules is included
at the end of this message.

======================================================================
AL-KERNEL CLASSIFICATION RESULT
======================================================================

CVE-2026-97475	MODERATE	https://www.kernelcve.org/list/?q=CVE-2026-97475 CHECK WITH IMPACT FROM ORIG NN MODERATE	Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:L/AC:H/PR:H/UI:N/S:U/C:L/I:L/A:H';*CWE-416;CWE-404;*CWE-664;Other CVSS 'AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H';BEST CVSS score: '5.2';DESCR 'A use after free condition can occur in the Tegra SoCTherm driver because cooling devices remain registered in the thermal framework after the platform driver is removed. Their devdata pointer can then reference freed driver state and a later thermal framework callback may dereference stale memory, causing a kernel crash or unstable kernel behavior. For the CVSS the PR:H value reflects that reliably creating the stale cooling device normally requires privileged driver unbind or removal operations. The issue is not network reachable. Impact is primarily local denial of service. Limited confidentiality or integrity impact is retained only for the paranoid score because this is a kernel use after free, but the patch does not demonstrate a controlled overwrite or a proven privilege escalation path.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate (with actual score 1)	YES	INIT ERRORPATH UAF HARDWARE DEBUGFS  DECREASED_TO_MODERATE_REGULAR_FROM_MODERATE7_BASED_ON_GUESSCVSS_AND_CIANNH	NO	NO	checked

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ACTIONABLESCORE ANALYSIS
======================================================================

ActionableScore=1
PrimitiveClass=CLASS_B
RealUAF=YES
HostAdminRequired=YES
NamespaceScopedPrivilege=NO
ImportantCandidate=NO
ManualReview=RECOMMENDED
AutoDowngradeAllowed=YES

1. ActionableScore

* Raw conservative score: 1
* Conservative score: 1
* Raw paranoid score: 1
* Paranoid score: 1
* Final recommended bucket: **Ordinary Moderate**::

The conservative and paranoid scores are identical because the supplied patch establishes a real stale lifetime condition, but does not establish controlled reclaim, attacker controlled replacement, a second release operation, a callback dispatch through reclaimed memory, disclosure, integrity impact, or privilege escalation.

2. Signal breakdown

* +2 Real UAF or active lifetime violation. The cooling devices remain registered in the thermal framework after the Tegra driver is removed. Their devdata pointer continues to reference ts after devm cleanup frees the associated driver state.
* +1 Plausible kernel crash or strong local DoS. A later cooling-device callback can dereference freed driver state through devdata. A kernel fault is a realistic consequence of this stale pointer.
* -2 Host-admin-equivalent privilege requirement. Reliably creating the stale state requires removing or unbinding the host Tegra platform driver. This is a host administrative operation.

Not awarded:

* No remote reachability bonus. The affected path is not reachable from network traffic.
* No local unprivileged trigger bonus. The complete stale-object creation sequence requires host driver removal.
* No attacker-influenced active-object lifetime manipulation bonus. The patch does not show attacker control over repeated object replacement, free timing, or post-free state.
* No structured stale-object leverage bonus. The known stale use is through thermal-framework cooling-device callbacks after driver teardown. The supplied context does not establish meaningful post-reuse consumption of attacker-influenced fields.
* No concrete repeated release or refcount mutation bonus. The patch shows a missing unregister operation, not a first release followed by a second put, free, or refcount mutation on the same dangling reference.
* No controlled reclaim, arbitrary write, callback hijack, confidentiality, integrity, or privilege-escalation bonus. None is established by the supplied patch.
* No additional Availability point. The possible kernel fault is already counted as the single DoS consequence.

3. Reachability analysis

The evaluated attacker is a host administrator or an equivalently privileged host process able to unbind or remove the Tegra SoCTherm platform driver. The stale devdata condition is created only after driver removal while the thermal framework still retains the cooling-device registration.

The supplied context does not show an ordinary local user, container user, or namespace-scoped capability holder performing the complete sequence. The relevant platform driver and its bind or unbind operation are host-owned. NamespaceScopedPrivilege is therefore NO.

This is Tegra-specific driver code, but no additional niche or hardware penalty is applied because the host-admin requirement already materially limits practical reachability. No race is required by the established sequence. The issue is an ordered teardown lifetime mismatch.

4. Primitive and severity interpretation

The exact primitive is a real post-lifetime stale-object use. The thermal framework retains thermal_cooling_device objects after removal of the Tegra driver, while their devdata field points to ts memory that devm cleanup has already freed.

This is an active structured-object UAF, but the supplied evidence supports only a constrained teardown scenario. It does not establish that an attacker can reclaim the freed ts allocation with controlled contents, cause type confusion, influence cooling-device callback operations after reuse, or obtain an arbitrary kernel read or write primitive.

There is no concrete repeated release or refcount mutation. This is therefore not the stronger case of:

A. first release may destroy an object followed by a second release through the same dangling reference.

Instead, it is:

B. a stale devdata pointer retained by a registered cooling device and later potentially dereferenced by thermal-framework activity.

The issue is CLASS_B because a real UAF is established. It is not CLASS_A because no controlled corruption or security-boundary primitive is shown. The demonstrated practical consequence is local kernel instability or crash after privileged driver removal. Privilege escalation remains speculative and is not scored.

ImportantCandidate is NO because the stale use occurs in a privileged driver-removal context and no meaningful post-free reuse or lifetime-mutation leverage is established. AutoDowngradeAllowed is YES because this is a constrained teardown UAF with crash or DoS as the supported consequence and without unresolved strong exploitation mechanics.

5. One-sentence report phrase

A Tegra SoCTherm driver removal could leave registered thermal cooling devices with devdata pointers to freed driver state, allowing a later thermal callback to cause a local kernel crash.

6. Manual review recommendation

MANUAL CHECK RECOMMENDED

A real UAF is explicitly described, so the cooling-device callback paths and driver-unbind reachability should be checked if Tegra platforms are in scope. The supplied evidence currently supports a host-admin-triggered local DoS rather than an Important-class exploitation primitive.

7. Call-site confidence

Call-site confidence: medium

======================================================================
UPSTREAM PATCH SUMMARY
======================================================================

Patch: thermal/drivers/tegra/soctherma: Switch to devm cooling device registration [ Upstream
Commit: 6f2a863e7e9adf6088fe644259576181e60ee5e5
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=6f2a863e7e9adf6088fe644259576181e60ee5e5

Changed files:
  drivers/thermal/tegra/soctherm.c

Diff excerpt:

Not included in this email. See the upstream URL for the full patch.

Full patch:
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=6f2a863e7e9adf6088fe644259576181e60ee5e5

======================================================================
DETAILED REPORT METHODOLOGY
======================================================================

The original Linux kernel CVE announcement for CVE-2026-97475 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-97475

The original CVE announcement normally does not include a security-level
estimate. In particular, it may not contain a CVSS assessment, an impact
level, or enough information to determine whether the reported bug is a
practically relevant security issue. One purpose of this parallel CVE list
is to provide that missing technical and prioritization information.

The original goal of the AL-KERNEL project was to prioritize Linux kernel
CVE analysis automatically before manual review. The system can also help
identify non-security issues that may be suitable for automatic closure.

This report was generated by AL-KERNEL, an AI-assisted Linux kernel
vulnerability analysis system developed by Alexander Larkin.

The first analysis stage combines an autonomous classifier with additional
LLM-based analysis. The autonomous classifier runs locally on a CPU and is
based on a backpropagation neural network. Together, these mechanisms
produce a technical vulnerability description, identify likely weakness
types, estimate CVSS severity, and provide input for ActionableScore.

Two CVSS estimates are retained because incomplete kernel vulnerability
information often permits more than one defensible interpretation:

  Conservative CVSS vector: AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H
  The Best / paranoid CVSS vector: AV:L/AC:H/PR:H/UI:N/S:U/C:L/I:L/A:H
  The Best / paranoid CVSS score: 5.2

The conservative vector represents a lower-impact interpretation.
The Best/paranoid vector intentionally represents a plausible upper-bound
interpretation and should not automatically be treated as demonstrated
real-world impact.

CVSS may also need to be adjusted for a particular Linux deployment,
because actual reachability, privileges, enabled kernel configuration,
hardware, namespaces, exposed device nodes, and other environmental
conditions can differ significantly between systems.

A separate ActionableScore mechanism evaluates practical remediation
urgency. Its analysis may include reachability, attack prerequisites,
subsystem exposure, memory-corruption characteristics, denial-of-service
reliability, and possible confidentiality, integrity, or
privilege-escalation impact.

  Conservative ActionableScore: unknown
  Paranoid ActionableScore: 1

The final base severity is taken directly from the second tab-separated
field of the AL-KERNEL classification result. ActionableScore does not
replace or independently override that final AL-KERNEL decision, and
if ActionableScore adjusted impact level of ALKERNEL, then you would see
self-readable flags above like INCREASED_TO_HIGH_BASED_ON_ACTIONABLESCOREHIGHEREQTHAN7.

For an AL-KERNEL result of MODERATE, this report uses the following
additional presentation split:

  ActionableScore below 5   -> MODERATE REGULAR
  ActionableScore 5 or more -> MODERATE 7.0

The distinction between MODERATE REGULAR and MODERATE 7.0 makes it
possible to identify Moderate issues that should receive manual analysis
and fixes before lower-priority MODERATE REGULAR issues. In many cases,
MODERATE REGULAR fixes may wait for a later rebase or routine update.

There is one override in which MODERATE REGULAR becomes MODERATE 7.0
even when the ActionableScore is below 5. When the AL-KERNEL result
contains the KPANIC flag, a MODERATE result is always presented as
MODERATE 7.0. The KPANIC flag selected with few regexps without
usage of AI at all, so it helps to detect cases when Kernel Crash happens
and similar (to filter False-Negative results from the LLM usage).

KPANIC indicates that a reliable kernel crash, kernel panic, or similarly
serious kernel availability impact was identified by the classification
workflow.

AL-KERNEL base severity for this report: MODERATE
KPANIC detected for this report: NO
Published priority for this report (same as in Subject): MODERATE REGULAR

These results are intended to support engineering triage. They are
machine-generated estimates, and cases marked for manual review should
be validated by a human security engineer before final disposition.
For more info read docs linked from here: https://kernelcve.org/
(and you can submit you own patch there to generate such a report
for non-existant CVE-id yet).

Note that in many cases this AI tool selects higher severity, than
real is (means you can expect Importants instead of Moderate 7.0 or
Moderates 7.0 instead of regular Moderates). If you see such cases,
please use reply email interface to add additional manual analyses
info to this particular CVE.
And please, please, let me know when you see Lows instead of Importants
or Important instead of Low (because particular for such cases I
need to tune this AI tool to make it better for this one and next similar).
My contact email for such notifications is alexanjelausa@gmail.com (and both
send reply to CVE record itself too and see "reply" button below for howto reply).