[CVE-2026-68371][MODERATE REGULAR] usb: musb: omap2430: Do not put borrowed of_node in probe [ Upstream

[CVE-2026-68371][MODERATE REGULAR] usb: musb: omap2430: Do not put borrowed of_node in probe [ Upstream

[AL-KERNEL]

CVE: CVE-2026-68371
Priority: MODERATE REGULAR
AL-KERNEL base severity: MODERATE
KPANIC flag: NO
Patch: usb: musb: omap2430: Do not put borrowed of_node in probe [ Upstream
Commit: eed56f105a7f70cbcfceb4df6deb6870fc58214d
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=eed56f105a7f70cbcfceb4df6deb6870fc58214d
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-68371
Analysis date: Mon, 10 Aug 2026 14:33:23 -0400
ActionableScore: 3
ActionableScore lower bound: 1
Actionable bucket: Borderline, manual review recommended
Manual review required: YES

Summary:
The omap2430 MUSB probe path incorrectly released a borrowed device-tree node reference, creating an OF node refcount imbalance that may cause stale pointer or UAF-style failures on dynamic OF systems, but exploitation is local, privileged, platform-specific, and not network reachable.

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

The original Linux kernel CVE announcement for CVE-2026-68371 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-68371

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: YES

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

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

CVE-2026-68371	MODERATE	CHECK WITH IMPACT FROM ORIG NN LOW	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-911;*CWE-416;*CWE-664;Other CVSS 'AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:L';BEST CVSS score: '5.2';DESCR 'omap2430_probe calls of_node_put on pdev dev of_node even though the pointer is borrowed and no reference was taken. This can corrupt the device tree node reference count and may leave the platform device holding a pointer whose lifetime is no longer protected. On systems with dynamic device tree nodes or overlays, later users of the same of_node could observe a stale object and a UAF style failure. For the CVSS the PR:H is used for the paranoid score because reliable triggering normally requires administrative control over driver probe, device binding, or device tree overlay state. The issue is local and platform specific. It is not network reachable. Impact is mainly availability, with limited confidentiality or integrity impact considered only for the paranoid UAF interpretation. YES REQUIRES MANUAL CHECK';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Borderline, manual review recommended (with actual score 2)  SKIP CVE-2026-68371 UNKNOWN SKIP No affected files built, so skip this CVE NO  - - unknown 	MAYBE	USB ERRORPATH HARDWARE LINUS  INCREASED_FROM_LOW_BASED_ON_REQUIREMANUALCHECK DECREASED_TO_MODERATEREG_BASED_ON_ACTIONABLESCORELESSTHAN5	-	-	checked

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

ActionableScore=3
ActionableScoreLower=1

## 1. ActionableScore

* Conservative score: 1
* Paranoid score: 3
* Final recommended bucket: **Borderline, manual review recommended**::

## 2. Signal breakdown

Conservative signals:

* Real lifetime corruption: +1. The driver calls `of_node_put()` on a borrowed `pdev->dev.of_node` pointer, causing an unbalanced device-tree node reference count.
* Requires admin/root/CAP level control in typical deployments: -2. Reliable triggering normally requires driver probe/unbind/rebind, platform-device control, module/device management, or device-tree overlay manipulation.
* Rare hardware/platform-specific condition: -1. This is specific to `usb: musb: omap2430` and relevant OMAP/MUSB platform-device setups.
* Privileged kernel/device-management lifetime path: +1. The bug occurs in driver probe/error handling and affects kernel-owned device lifetime state.

Paranoid additional signals:

* Memory corruption, weak/indirect corruption candidate: +1. The refcount imbalance can theoretically leave `pdev->dev.of_node` pointing to an object whose lifetime is no longer protected, especially with dynamic OF or overlays.
* Availability impact plausible: +1. A stale OF node pointer or refcount imbalance can plausibly lead to crashes or probe/remove instability.
* Confidentiality impact plausible: +1 and Integrity impact plausible: +1 are only weakly considered in the paranoid interpretation because a UAF-style lifetime failure exists, but no attacker-controlled reclaim, overwrite, callback control, or info leak is shown.

No remote/network signal applies. No strong LPE signal applies. No strong memory-corruption primitive is demonstrated.

## 3. Reachability analysis

The bug is local and platform-specific. A practical trigger normally requires administrative control over the affected OMAP/MUSB platform device lifecycle, such as driver probe failure paths, bind/unbind, module/device management, or dynamic device-tree overlay activity.

Namespaces and containers do not materially lower the privilege requirement in typical deployments because platform device probing and OF overlay manipulation are host-level administrative operations. The path is not network reachable and is not a common default-exposed attack surface. Realistic exploitation conditions are narrow, but the lifetime/refcount nature of the bug makes it worth manual review if the product uses dynamic OF, overlays, or hotplug-like platform-device workflows.

Call-site confidence: medium. The changed call sites are visible, but downstream stale-node reuse depends on platform and OF lifetime behavior outside the small patch.

## 4. Severity interpretation

This behaves more like a low-to-borderline Moderate lifetime-management bug than an Important-class vulnerability. The conservative view is a privileged, platform-specific reference-count imbalance with possible local DoS. The paranoid view treats it as a weak UAF candidate because dropping a borrowed OF node reference can invalidate lifetime assumptions for `pdev->dev.of_node`.

There is theoretical memory-corruption potential, but no realistic exploitation evidence for privilege escalation, controlled reclaim, arbitrary write, type confusion, or information disclosure is shown by the patch.

## 5. One-sentence report phrase

The omap2430 MUSB probe path incorrectly released a borrowed device-tree node reference, creating an OF node refcount imbalance that may cause stale pointer or UAF-style failures on dynamic OF systems, but exploitation is local, privileged, platform-specific, and not network reachable.

## 6. Manual review recommendation

MANUAL CHECK RECOMMENDED

Reason: the issue is not urgent Important-class based on the patch alone, but it is a real lifetime/refcount bug with a plausible UAF-style failure mode on dynamic OF or overlay-enabled systems.

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

Patch: usb: musb: omap2430: Do not put borrowed of_node in probe [ Upstream
Commit: eed56f105a7f70cbcfceb4df6deb6870fc58214d
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=eed56f105a7f70cbcfceb4df6deb6870fc58214d

Changed files:
  drivers/usb/musb/omap2430.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=eed56f105a7f70cbcfceb4df6deb6870fc58214d

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

The original Linux kernel CVE announcement for CVE-2026-68371 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-68371

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:L
  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: 1
  Paranoid ActionableScore: 3

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).