[CVE-2026-98795][MODERATE REGULAR] net: sparx5: skip ptp deinit if init was skipped [ Upstream

[CVE-2026-98795][MODERATE REGULAR] net: sparx5: skip ptp deinit if init was skipped [ Upstream

[AL-KERNEL]

CVE: CVE-2026-98795
Priority: MODERATE REGULAR
AL-KERNEL base severity: MODERATE
KPANIC flag: NO
Patch: net: sparx5: skip ptp deinit if init was skipped [ Upstream
Commit: 35c706d6eb1963735814c5f5bb2674a96eacf3cc
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=35c706d6eb1963735814c5f5bb2674a96eacf3cc
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98795
Analysis date: Sat, 24 Oct 2026 03:18:09 -0400
ActionableScore: 0
ActionableScore lower bound: unknown
Actionable bucket: Ordinary Moderate
Manual review required: NO

Summary:
Administrative removal of a Sparx5 device can dereference uninitialized PTP queue state and cause a kernel Oops when PTP initialization was skipped.

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

The original Linux kernel CVE announcement for CVE-2026-98795 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98795

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-2026-98795	MODERATE	https://www.kernelcve.org/list/?q=CVE-2026-98795 CHECK WITH IMPACT FROM ORIG NN MODERATE | AEGIS IMPACT MODERATE AEGIS_AS=0 LEGACY=MODERATE RESULT=SAME V39_AEGIS_ONE_STEP_UP=LOW->MODERATE (final reconciliation agrees; DECISION: both MODERATE)	Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H';**CWE-476;CWE-665;Other CVSS 'AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:L';BEST CVSS score: '5.5';DESCR 'sparx5_ptp_deinit can purge uninitialized tx_skbs queues when sparx5_ptp_init was skipped because PTP is unsupported or no ptp interrupt was provided. The demonstrated primitive is a NULL pointer dereference during driver unbind and not UAF or controlled memory corruption. For the CVSS the PR:H base value reflects that unbinding this platform driver normally requires administrative privileges. For the CVSS the PR:L paranoid value covers delegated device management or a reduced capability service that can request driver removal. The base impact is a kernel oops and failed device removal. A host wide crash is plausible when panic_on_oops is enabled, but there is no evidence of confidentiality or integrity impact and no direct packet based trigger. Automated impact decision path. The original SimpleNet classifier selected MODERATE_KPANIC. The primary LLM estimated paranoid CVSS 5.5 and the production ActionableScore returned 0 with recommendation Ordinary Moderate. The production rules then evaluated CVSS thresholds and ActionableScore thresholds. Recorded rule transitions were CVSS and initial triage stage MODERATE_KPANIC to MODERATE because the CVSS score, vector or bug class threshold rule was applied. ActionableScore thresholds stage MODERATE to LOW because the ActionableScore threshold rule was applied. final reconciliation stage LOW to MODERATE because the cross model evidence reconciliation rule was applied. The legacy KP specialist has no review artifact for this run. The legacy FD or DH downgrade specialist has no review artifact for this run. Exact triggered rule markers were DECREASED_TO_MODERATE_REGULAR_FROM_MODERATE7_BASED_ON_GUESSCVSS_AND_CIANNH and DECREASED_TO_LOW_FROM_MODERATE_BASED_ON_ACTIONABLESCORELESSTHAN3 and V39_AEGIS_ONE_STEP_UP and MANUAL_REVIEW_REQUIRED. The independent weaker Aegis shadow evaluated CVSS 2.4 and ActionableScore 0 with primitive class CLASS_C and manual review REQUIRED. Its independently reconciled impact was MODERATE. Cross model aggregation changed the production result under an enabled evidence gated merge rule. The final reported impact is MODERATE.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate (with actual score 0)	MAYBE	REMOTE OOB NULLPTR SIMPLEFIX NETWORK HARDWARE LINUS DECREASED_TO_MODERATE_REGULAR_FROM_MODERATE7_BASED_ON_GUESSCVSS_AND_CIANNH DECREASED_TO_LOW_FROM_MODERATE_BASED_ON_ACTIONABLESCORELESSTHAN3 V39_AEGIS_ONE_STEP_UP MANUAL_REVIEW_REQUIRED	-	-	checked

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

ActionableScore=0
PrimitiveClass=CLASS_C
RealUAF=NO
HostAdminRequired=YES
NamespaceScopedPrivilege=NO
ImportantCandidate=NO
ManualReview=NO
AutoDowngradeAllowed=YES
RequiresHostUID0=UNKNOWN
AuthorizationDecisionBypass=NO
ProtectedResourceImpact=NONE
B4PendingReview=NO
B4PendingConfirmed=NO

1. ActionableScore

* Raw base score: -1.
* Conservative score: 0 after clamping the negative result to the minimum score.
* Raw paranoid score: -1.
* Paranoid score: 0 after clamping.
* Final recommended bucket: **Ordinary Moderate**::

2. Signal breakdown

* +1 Reliable kernel crash/strong DoS: driver removal calls `sparx5_ptp_deinit()` after initialization was skipped, and queue purge dereferences uninitialized state at address `0x8`. An Oops is demonstrated; panic is configuration-dependent.
* -2 Proven host-administrator-equivalent operation: the shown trigger is unbinding/removing a platform Ethernet driver. No below-host-admin device-removal interface is established.
* No UAF, OOB write, repeated release, active-state corruption, authorization bypass, information disclosure, or integrity primitive is shown.
* No extra availability point: failed removal and the Oops are consequences of the same fault.
* No B5-R retry-accumulated OOB write or B3 shared-backing write exists.
* Delegated device management is only hypothetical and therefore does not alter the score or privilege classification.

3. Reachability analysis

The vulnerable path is reached during platform-driver unbind/removal, not through packet reception or ordinary network traffic. The evidence supports administrative device lifecycle control as the complete trigger. Numeric UID 0 is not strictly established because equivalent capability-based administration may suffice. No namespace-scoped trigger, prior delegation, race, retry sequence, or attacker-controlled payload is shown. Applicable Sparx5/LAN969x hardware and a skipped PTP initialization path are required.

4. Primitive and severity reading

The exact primitive is a NULL-pointer dereference while purging never-initialized per-port SKB queues. This is invalid-state consumption during teardown, not stale post-lifetime storage or a second lifetime mutation. The fix records no new protection boundary; it simply skips deinitialization when PTP was never initialized.

The demonstrated effect is a kernel Oops and failed device removal, with possible host panic under `panic_on_oops`. Non-crash exploitation, memory corruption, confidentiality impact, and integrity impact are unsupported. This is CLASS_C, not an Important candidate, and ordinary downgrade is safe.

5. One-sentence report phrase

Administrative removal of a Sparx5 device can dereference uninitialized PTP queue state and cause a kernel Oops when PTP initialization was skipped.

6. Manual review advice

NO MANUAL CHECK NEEDED

The patch establishes a privileged teardown NULL dereference without a separate corruption or security-boundary primitive.

7. Call-site confidence

Call-site confidence: high

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

Patch: net: sparx5: skip ptp deinit if init was skipped [ Upstream
Commit: 35c706d6eb1963735814c5f5bb2674a96eacf3cc
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=35c706d6eb1963735814c5f5bb2674a96eacf3cc

Changed files:
  drivers/net/ethernet/microchip/sparx5/sparx5_ptp.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=35c706d6eb1963735814c5f5bb2674a96eacf3cc

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

The original Linux kernel CVE announcement for CVE-2026-98795 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98795

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:L/PR:H/UI:N/S:U/C:N/I:N/A:L
  The Best / paranoid CVSS vector: AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
  The Best / paranoid CVSS score: 5.5

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: 0

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).