[CVE-2026-72092][MODERATE REGULAR] accel/amdxdna: reject command submission on devices without a submit op [ Upstream commit 38953513d7313992676d4136cd425cdb70c6278e ]

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

CVE: CVE-2026-72092
Priority: MODERATE REGULAR
AL-KERNEL base severity: MODERATE
KPANIC flag: NO
Patch: accel/amdxdna: reject command submission on devices without a submit op [ Upstream commit 38953513d7313992676d4136cd425cdb70c6278e ]
Commit: af7a4c2caa7a191d6e7ed33903b69f9901874cd0
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=af7a4c2caa7a191d6e7ed33903b69f9901874cd0
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-72092
Analysis date: Sat, 15 Aug 2026 19:41:52 -0400
ActionableScore: 3
ActionableScore lower bound: 2
Actionable bucket: Borderline Moderate / manual review recommended
Manual review required: YES

Summary:
A local user with access to an affected AMD XDNA AIE4 SR-IOV VF device can issue AMDXDNA_EXEC_CMD and trigger a NULL function-pointer call in amdxdna_cmd_submit, causing a kernel crash or oops.

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

The original Linux kernel CVE announcement for CVE-2026-72092 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-72092

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.

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AL-KERNEL CLASSIFICATION RESULT
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CVE-2026-72092	MODERATE	CHECK WITH IMPACT FROM ORIG NN LOW	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-754;CWE-703;BEST CVSS score: '5.5';DESCR 'amdxdna_cmd_submit calls the device cmd_submit callback without checking whether the callback exists. On AIE4 SR IOV VF devices the shared AMDXDNA_EXEC_CMD ioctl can therefore reach a NULL function pointer call because this device type submits work through a mapped user queue and doorbell instead of this ioctl path. A local user with access to the AMD XDNA accelerator device node can trigger a kernel oops or panic by issuing the EXEC_CMD ioctl on an affected device. For the CVSS the PR:L is used because reliable triggering requires a local process with access to the device node, but this access may be available to non root users through render or accelerator device permissions. The issue is not network reachable. Impact is denial of service via kernel crash. No practical confidentiality or integrity impact is indicated because the primitive is a NULL function pointer call rather than UAF, OOB write, or controllable memory corruption.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Borderline Moderate / manual review recommended (with actual score 3)  SKIP CVE-2026-72092 UNKNOWN SKIP No affected files built, so skip this CVE NO  - - unknown 	MAYBE	SIMPLEFIX HARDWARE  INCREASED_FROM_LOW_BASED_ON_REQUIREMANUALCHECK DECREASED_TO_MODERATEREG_BASED_ON_ACTIONABLESCORELESSTHAN5	-	-	checked

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ACTIONABLESCORE ANALYSIS
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ActionableScore=3
ActionableScoreLower=2

## 1. ActionableScore

* Conservative score: 2
* Paranoid score: 3
* Final recommended bucket: **Borderline Moderate / manual review recommended**

## 2. Signal breakdown

Conservative signals:

* Local unprivileged trigger: +1. A local user can trigger the ioctl if they have access to the AMD XDNA accel device node, which may be granted to non-root users via render or accelerator device permissions.
* Reliable kernel crash / strong DoS: +1. The missing callback check can lead to a NULL function-pointer call and kernel oops or panic.
* Availability impact realistic: +1. The trigger is a simple ioctl on an affected device and can plausibly cause host availability impact.
* Rare hardware-specific condition: -1. The issue is limited to AMD XDNA AIE4 SR-IOV VF devices where cmd_submit is absent.

Paranoid difference:

* The paranoid score omits the rare-hardware penalty for environments where affected AIE4 VF devices are actually deployed and exposed to users.

Not awarded:

* Generic memory corruption: +0. This is a NULL function-pointer call to address zero, not UAF, OOB write, type confusion, or controllable overwrite.
* Privilege escalation plausible: +0. No reclaim, callback control, arbitrary write, or object replacement primitive is shown.
* Remote reachable: +0. The affected path is a local ioctl, not a network path.

## 3. Reachability analysis

The bug is reachable by a local process that can open the AMD XDNA accelerator device and issue AMDXDNA_EXEC_CMD on an affected AIE4 SR-IOV VF device. It does not require network access and is not remotely triggerable by packet traffic. Namespaces or containers matter only if the device node is passed through or device cgroup policy allows access. In typical deployments, exposure depends heavily on hardware presence and device-node permissions.

Call-site confidence: high, because the patch and commit message identify the direct ioctl path and the exact NULL callback dereference.

## 4. Severity interpretation

This behaves like a local DoS issue rather than an Important-class memory corruption vulnerability. The theoretical severity is limited because the primitive is a NULL function-pointer call, not attacker-controlled function-pointer corruption. Realistic impact is kernel oops or panic from a local device ioctl. It should not be auto-escalated to LPE without additional evidence.

## 5. One-sentence report phrase

A local user with access to an affected AMD XDNA AIE4 SR-IOV VF device can issue AMDXDNA_EXEC_CMD and trigger a NULL function-pointer call in amdxdna_cmd_submit, causing a kernel crash or oops.

## 6. Manual review recommendation

MANUAL CHECK RECOMMENDED

Manual review is recommended to confirm affected hardware exposure and device-node permissions, but this does not currently look like a strong Important candidate because no practical memory corruption or privilege-escalation primitive is shown.

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

Patch: accel/amdxdna: reject command submission on devices without a submit op [ Upstream commit 38953513d7313992676d4136cd425cdb70c6278e ]
Commit: af7a4c2caa7a191d6e7ed33903b69f9901874cd0
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=af7a4c2caa7a191d6e7ed33903b69f9901874cd0

Commit description:

amdxdna_cmd_submit() calls xdna->dev_info->ops->cmd_submit()
unconditionally, but only aie2_dev_ops defines that callback.
aie4_vf_ops (the AIE4 SR-IOV virtual function) does not, so a user
AMDXDNA_EXEC_CMD ioctl on an AIE4 device reaches a NULL function-pointer
call and oopses the kernel. AIE4 submits work through a mapped user queue
and doorbell, not this ioctl path.

Reject the submission early with -EOPNOTSUPP when the device provides no
cmd_submit op, so the shared EXEC ioctl is a clean no-op on such devices.

Fixes: aac243092b70 ("accel/amdxdna: Add command execution")
Cc: stable@vger.kernel.org
Found by 0sec automated security-research tooling (https://0sec.ai).
Assisted-by: 0sec:claude-opus-4-8
Signed-off-by: Doruk Tan Ozturk <doruk@0sec.ai>
Reviewed-by: Lizhi Hou <lizhi.hou@amd.com>
Signed-off-by: Lizhi Hou <lizhi.hou@amd.com>
Link: https://patch.msgid.link/20260713173030.87541-3-doruk@0sec.ai
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat -rw-r--r-- drivers/accel/amdxdna/amdxdna_ctx.c 4

Changed files:
  drivers/accel/amdxdna/amdxdna_ctx.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=af7a4c2caa7a191d6e7ed33903b69f9901874cd0

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

The original Linux kernel CVE announcement for CVE-2026-72092 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-72092

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: Not available
  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: 2
  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).