[CVE-2026-74265][LOW] net: mana: initialize gdma queue id to INVALID_QUEUE_ID [ Upstream

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

CVE: CVE-2026-74265
Priority: LOW
AL-KERNEL base severity: LOW
KPANIC flag: NO
Patch: net: mana: initialize gdma queue id to INVALID_QUEUE_ID [ Upstream
Commit: 372e7318af379eee29ab6e60848ce7d7db76c85a
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=372e7318af379eee29ab6e60848ce7d7db76c85a
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-74265
Analysis date: Sat, 15 Aug 2026 03:06:10 -0400
ActionableScore: 2
ActionableScore lower bound: 0
Actionable bucket: Ordinary Moderate / Low-like auto-close candidate
Manual review required: NO

Summary:
A MANA GDMA queue creation error path can leave a newly allocated queue with id 0, causing cleanup to clear an unrelated CQ table entry and potentially break the network device, but exploitation appears limited to privileged or firmware-mediated local device-management scenarios.

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

The original Linux kernel CVE announcement for CVE-2026-74265 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-74265

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: LOW
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
======================================================================

CVE-2026-74265	LOW	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:L/UI:N/S:U/C:N/I:N/A:H';CWE-665;CWE-703;CWE-754;**CWE-476;Other CVSS 'AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:L';BEST CVSS score: '4.7';DESCR 'MANA GDMA work queue CQ creation can leave queue id equal to zero before the firmware returns a real queue id. If creation fails before that assignment, cleanup can destroy CQ id 0 and clear gc cq_table 0, silently breaking an unrelated real completion queue that owns that slot. This is mainly an internal driver state corruption and availability issue rather than a proven memory corruption primitive. For the CVSS the PR:L is used in the paranoid score because a reduced-capability local service, container root, or delegated network administration context may be able to trigger reset or queue setup failure paths in some deployments. The issue is not directly network reachable and does not appear to be triggered by ordinary packet traffic alone. Impact is denial of service through broken device state or possible later NULL dereference, with no clear evidence of confidentiality impact, integrity impact, or privilege escalation.';NO MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate / Low-like auto-close candidate (with actual score 1)	YES	REMOTE SIMPLEFIX NETWORK  DECREASED_TO_MODERATE_REGULAR_FROM_MODERATE7_BASED_ON_GUESSCVSS_AND_CIANNH DECREASED_TO_LOW_FROM_MODERATE_BASED_ON_ACTIONABLESCORELESSTHAN3	NO	NO	checked

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

ActionableScore=2
ActionableScoreLower=0

## 1. ActionableScore

* Conservative score: 0
* Paranoid score: 2
* Final recommended bucket: **Ordinary Moderate / Low-like auto-close candidate**::

## 2. Signal breakdown

Conservative signals:

* Firmware-mediated external influence: +1. The bad cleanup path depends on WQ/CQ creation failing before firmware returns a real queue id.
* Availability impact realistic: +1. Clearing `gc->cq_table[0]` can break an unrelated real CQ and disrupt the MANA device.
* Requires admin/root/CAP_* in typical deployments: -2. Reliable triggering normally requires driver load, reset, device recovery, or privileged device-management paths.

Conservative total: `1 + 1 - 2 = 0`

Paranoid signals:

* Firmware-mediated external influence: +1. Firmware rejection or failure can expose the buggy pre-id-assignment cleanup path.
* Weak/indirect corruption candidate: +1. Cleanup uses a bogus default id 0 and modifies the wrong CQ table slot, but no attacker-controlled payload or arbitrary target is shown.
* Privileged kernel/device-management state corruption path: +1. The bug corrupts trusted driver queue bookkeeping during a privileged device-management/error path.
* Reliable device DoS concern: +1. Breaking a live CQ can plausibly cause device malfunction or later NULL dereference.
* Corruption primitive highly constrained or metadata-only: -1. The affected write is a bounded table NULL assignment, not an arbitrary write.
* Requires privileged or delegated device control: -1. Paranoid scoring allows reduced-capability service or delegated admin contexts, but this is still not a normal unprivileged local trigger.

Paranoid total: `1 + 1 + 1 + 1 - 1 - 1 = 2`

## 3. Reachability analysis

The bug is local and device-management/error-path oriented. It is not directly reachable through ordinary network packets. A realistic trigger requires MANA device initialization, reset, recovery, or queue creation failure before `mana_create_wq_obj()` assigns the firmware-returned id.

Namespaces and containers do not obviously make this reachable by an unprivileged user. A paranoid interpretation can consider container root, reduced-capability service accounts, or delegated network/device-management roles, but the patch does not show a normal unprivileged interface.

The affected hardware is Microsoft Azure MANA, so exposure is important in Azure environments but not broad/default on generic Linux systems.

Call-site confidence: medium. The commit clearly describes the cleanup consequence, but the full caller/error-unwind graph is not included in the provided diff.

## 4. Severity interpretation

This behaves like an ordinary Moderate or Low-like driver DoS/state-corruption issue, not an Important-class vulnerability. The patch shows wrong-object cleanup of CQ id 0 and driver internal table corruption, but not UAF, double free, OOB write, arbitrary write, attacker-controlled reclaim, information leak, or privilege escalation.

Theoretical impact can include device malfunction or a later NULL dereference. Realistic exploitation evidence supports availability impact only.

## 5. One-sentence report phrase

A MANA GDMA queue creation error path can leave a newly allocated queue with id 0, causing cleanup to clear an unrelated CQ table entry and potentially break the network device, but exploitation appears limited to privileged or firmware-mediated local device-management scenarios.

## 6. Manual review recommendation

NO MANUAL CHECK NEEDED

This can be auto-closed for default prioritization because the actionable score is below 3, the bug is not network-triggerable, and the patch does not support memory corruption or privilege escalation beyond constrained driver bookkeeping corruption.

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

Patch: net: mana: initialize gdma queue id to INVALID_QUEUE_ID [ Upstream
Commit: 372e7318af379eee29ab6e60848ce7d7db76c85a
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=372e7318af379eee29ab6e60848ce7d7db76c85a

Changed files:
  drivers/net/ethernet/microsoft/mana/gdma_main.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=372e7318af379eee29ab6e60848ce7d7db76c85a

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

The original Linux kernel CVE announcement for CVE-2026-74265 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-74265

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:L/UI:N/S:U/C:N/I:N/A:H
  The Best / paranoid CVSS score: 4.7

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: 0
  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: LOW
KPANIC detected for this report: NO
Published priority for this report (same as in Subject): LOW

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).