[CVE-2026-64225][MODERATE REGULAR] octeontx2-af: CGX: add bounds check to cgx_speed_mbps index [ Upstream

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

CVE: CVE-2026-64225
Priority: MODERATE REGULAR
AL-KERNEL base severity: MODERATE
KPANIC flag: NO
Patch: octeontx2-af: CGX: add bounds check to cgx_speed_mbps index [ Upstream
Commit: 94071141f00bc414e8f8f7f5db3b5143d535299f
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=94071141f00bc414e8f8f7f5db3b5143d535299f
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-64225
Analysis date: Fri, 24 Jul 2026 12:43:32 -0400
ActionableScore: 2
ActionableScore lower bound: 1
Actionable bucket: Ordinary Moderate / Low-like
Manual review required: NO

Summary:
An out-of-bounds read in the octeontx2-af CGX link-status path can occur when firmware reports a speed index outside the 13-entry cgx_speed_mbps table, causing an incorrect reported speed and at most limited adjacent-data exposure on affected hardware.

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ABOUT THIS REPORT
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The original Linux kernel CVE announcement for CVE-2026-64225 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-64225

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.

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AL-KERNEL CLASSIFICATION RESULT
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CVE-2026-64225	MODERATE	CHECK WITH IMPACT FROM ORIG NN IMPORTANT	Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L';CWE-125;CWE-129;*CWE-20;Other CVSS 'AV:L/AC:H/PR:H/UI:N/S:U/C:L/I:N/A:N';BEST CVSS score: '4.2';DESCR 'An out of bounds read in the octeontx2-af CGX link status path can occur because RESP_LINKSTAT_SPEED may decode to values 13 through 15 while cgx_speed_mbps has only 13 entries. The invalid value is used as an array index and the read result is copied into linfo speed, so the realistic impact is an incorrect reported link speed and a possible small information exposure from adjacent constant data. For the CVSS the PR:N is used for the paranoid case because a directly attached link peer, faulty firmware path, or device controlled status source may influence the link status without a local login on the host. The issue is not reachable through ordinary routable packet traffic and exploitation is hardware and firmware dependent. Impact is limited to low confidentiality impact and possible availability degradation, with no evidence of privilege escalation or memory write corruption.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate / Low-like (with actual score 2)	YES	REMOTE OOB SIMPLEFIX NETWORK LINUS  LOWERED_FROM_HIGH_BASED_ON_GUESSCVSS  DECREASED_TO_MODERATEREG_BASED_ON_ACTIONABLESCORELESSTHAN5	YES	NO	checked

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ACTIONABLESCORE ANALYSIS
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ActionableScore=2
ActionableScoreLower=1

## 1. ActionableScore

* Conservative score: 1
* Paranoid score: 2
* Final recommended bucket: **Ordinary Moderate / Low-like**

## 2. Signal breakdown

Conservative signals:

* Confidentiality impact plausible: +1
  The bug is an out-of-bounds array read from `cgx_speed_mbps`. The read value is copied into `linfo->speed`, so a very small adjacent-data exposure is theoretically possible.
* Rare / hardware-specific exposure: -1
  The affected path is specific to Marvell OcteonTX2 CGX link-status handling and depends on firmware or hardware returning an invalid speed encoding.

Paranoid additional signal:

* Firmware-mediated external influence: +1
  `RESP_LINKSTAT_SPEED` is derived from link status reported through the CGX firmware / hardware path. A faulty firmware path or directly attached link environment might influence the invalid value without local code execution on the host.

Signals not applied:

* No strong memory corruption bonus. This is an OOB read, not an OOB write, UAF, double-free, refcount bug, or type confusion.
* No LPE bonus. The patch does not show attacker-controlled reclaim, overwrite, callback control, arbitrary write, or object confusion.
* No reliable DoS bonus. The most likely result is an incorrect speed value, not a demonstrated crash or persistent device failure.
* No remote network-triggerable bonus. This is not reachable through normal routable packet traffic.

## 3. Reachability analysis

The invalid index comes from CGX link-status data, not from a normal socket or packet-processing path. A local unprivileged user does not appear to have a direct interface to set `RESP_LINKSTAT_SPEED`. Realistic triggering requires specific OcteonTX2 hardware and a firmware or hardware status path that can report values 13 through 15.

A directly attached peer or abnormal link / firmware behavior may be relevant, but this is better modeled as firmware-mediated or hardware-adjacent influence rather than ordinary remote network reachability. Namespaces and containers do not materially lower the privilege requirement because the affected data originates below ordinary namespace-visible networking APIs.

Path default exposure is limited to systems using the affected Marvell OcteonTX2 AF CGX driver.

Call-site confidence: medium. The changed function and immediate use of the OOB value are visible, but broader user-visible propagation of `linfo->speed` is inferred from driver link-status reporting behavior.

## 4. Severity interpretation

This behaves like an ordinary Moderate / Low-like kernel driver bug rather than an Important-class vulnerability. The theoretical issue is a bounded OOB read from a small static speed table, with possible low confidentiality impact if adjacent constant data becomes observable as a bogus speed value.

Realistic exploitation evidence is weak. There is no write primitive, no UAF, no object lifetime corruption, no privilege escalation path, and no demonstrated kernel crash. The main reason not to fully auto-close without review is that it is a concrete kernel OOB read in a firmware-fed driver path.

## 5. One-sentence report phrase

An out-of-bounds read in the octeontx2-af CGX link-status path can occur when firmware reports a speed index outside the 13-entry cgx_speed_mbps table, causing an incorrect reported speed and at most limited adjacent-data exposure on affected hardware.

## 6. Manual review recommendation

MANUAL CHECK RECOMMENDED

Reason: the issue is low severity and hardware-specific, but it is still a concrete OOB read in kernel driver code with firmware-mediated input, so a lightweight manual check is appropriate before auto-closing.

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

Patch: octeontx2-af: CGX: add bounds check to cgx_speed_mbps index [ Upstream
Commit: 94071141f00bc414e8f8f7f5db3b5143d535299f
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=94071141f00bc414e8f8f7f5db3b5143d535299f

Changed files:
  drivers/net/ethernet/marvell/octeontx2/af/cgx.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=94071141f00bc414e8f8f7f5db3b5143d535299f

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

The original Linux kernel CVE announcement for CVE-2026-64225 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-64225

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:L/I:N/A:N
  The Best / paranoid CVSS vector: AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L
  The Best / paranoid CVSS score: 4.2

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: 2

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).