[CVE-2026-68308][MODERATE REGULAR] wifi: mt76: mt7996: check pointer returned by mt76_connac_get_he_phy_cap() [ Upstream

[CVE-2026-68308][MODERATE REGULAR] wifi: mt76: mt7996: check pointer returned by mt76_connac_get_he_phy_cap() [ Upstream

[AL-KERNEL]

CVE: CVE-2026-68308
Priority: MODERATE REGULAR
AL-KERNEL base severity: MODERATE
KPANIC flag: NO
Patch: wifi: mt76: mt7996: check pointer returned by mt76_connac_get_he_phy_cap() [ Upstream
Commit: 4fd85fd2373501b7386e93a5ce4a549d7c4e64e3
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=4fd85fd2373501b7386e93a5ce4a549d7c4e64e3
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-68308
Analysis date: Mon, 10 Aug 2026 12:04:02 -0400
ActionableScore: 3
ActionableScore lower bound: 1
Actionable bucket: Borderline, manual review recommended
Manual review required: YES

Summary:
A NULL pointer dereference in the mt7996 Wi-Fi driver may occur when mt76_connac_get_he_phy_cap() returns NULL during BSS or station HE setup, causing a kernel crash, with practical risk depending on whether the path is reachable only by local Wi-Fi administration or also by adjacent wireless peer interaction.

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

The original Linux kernel CVE announcement for CVE-2026-68308 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-68308

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
======================================================================

CVE-2026-68308	MODERATE	CHECK WITH IMPACT FROM ORIG NN MODERATE	Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H';**CWE-476;CWE-252;CWE-703;Other CVSS 'AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H';BEST CVSS score: '5.3';DESCR 'A NULL pointer dereference can occur in the mt7996 Wi-Fi driver because mt76_connac_get_he_phy_cap() may return NULL and the returned HE capability pointer was used in BSS and station setup paths. A local administrator can typically reach the vulnerable path through wireless interface or BSS configuration. A more conservative adjacent-network interpretation is also defensible because station setup paths may be reached when a nearby Wi-Fi peer interacts with an affected AP configuration. For the CVSS the PR:N is used in the paranoid score because the higher risk interpretation assumes no privileges beyond adjacent wireless reachability to the affected Wi-Fi service. The issue requires specific MediaTek mt7996 hardware and a configuration where the HE PHY capability lookup can fail, so AC:H is kept. Impact is denial of service via kernel oops or panic, with no supported evidence of confidentiality impact, integrity impact, or privilege escalation.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Borderline, manual review recommended (with actual score 2)  SKIP CVE-2026-68308 UNKNOWN SKIP No affected files built, so skip this CVE NO  - - unknown 	MAYBE	REMOTE SIMPLEFIX NETWORK HARDWARE  DECREASED_TO_MODERATE_REGULAR_FROM_MODERATE7_BASED_ON_GUESSCVSS_AND_CIANNH	-	-	checked

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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 scoring:

* Reliable kernel crash / strong DoS: +1
  The patch prevents a NULL pointer dereference in mt7996 driver code. If reached, this can cause kernel oops or panic.
* Requires admin/root/CAP_NET_ADMIN in typical deployments: -2
  The most reliable trigger appears to be through Wi-Fi interface, BSS, or driver configuration paths, normally requiring administrative network control.
* Floor applied for kernel crash relevance: final conservative score kept at 1 rather than negative.

Paranoid scoring:

* Remote reachable / network-triggerable: +2
  Only for the higher-risk interpretation. One affected path is station setup related, so a nearby Wi-Fi peer may influence execution if the device is operating in an affected AP configuration.
* Reliable kernel crash / strong DoS: +1
  The failure mode is a NULL pointer dereference in kernel driver code.
* No generic memory corruption: +0
  This is an invalid NULL dereference, not UAF, double free, OOB write, type confusion, arbitrary write, or refcount abuse.
* No privilege escalation plausible: +0
  The patch does not show attacker-controlled reclaim, object replacement, write-after-free, callback control, or a corruption sink.
* No C/I impact: +0
  No information disclosure or integrity primitive is supported by the patch.
* No rare-hardware subtraction applied in paranoid score.
  The bug is hardware-specific to mt7996, but Wi-Fi AP deployments are realistic enough that this should not be dismissed automatically.

## 3. Reachability analysis

The conservative trigger is local administrative control over the affected MediaTek mt7996 Wi-Fi device, such as configuring a BSS or changing wireless state. In typical Linux deployments this requires CAP_NET_ADMIN or equivalent host-level network administration privileges.

The paranoid interpretation is adjacent-network reachability. Because one fixed path is related to station HE beamforming setup, a nearby Wi-Fi peer may help reach the vulnerable code path when the affected AP configuration is present. This is not the same as Internet remote reachability. It depends on specific hardware, driver state, HE capability lookup behavior, and AP or station setup conditions.

Namespaces can matter only if CAP_NET_ADMIN over the real wireless device is delegated, which is uncommon for physical Wi-Fi hardware. Containers usually do not get direct safe access to host Wi-Fi device management.

## 4. Severity interpretation

This behaves more like a borderline Moderate issue than an Important kernel vulnerability. The realistic impact is DoS through NULL pointer dereference. There is no supported evidence of memory corruption beyond invalid dereference, no UAF, no write primitive, and no plausible LPE chain from the patch.

The reason it should not be fully auto-closed is the adjacent wireless trigger hypothesis. If a nearby unauthenticated peer can reliably trigger the station setup path on affected hardware, the operational risk is higher than an ordinary local privileged driver crash.

## 5. One-sentence report phrase

A NULL pointer dereference in the mt7996 Wi-Fi driver may occur when mt76_connac_get_he_phy_cap() returns NULL during BSS or station HE setup, causing a kernel crash, with practical risk depending on whether the path is reachable only by local Wi-Fi administration or also by adjacent wireless peer interaction.

## 6. Manual review recommendation

MANUAL CHECK RECOMMENDED

Manual review is recommended because the patch fixes a kernel NULL dereference in a wireless driver and there is a defensible adjacent-network reachability hypothesis, but the currently supported impact remains DoS only and does not justify Important-class handling without evidence of reliable peer-triggered reachability or memory corruption.

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

Patch: wifi: mt76: mt7996: check pointer returned by mt76_connac_get_he_phy_cap() [ Upstream
Commit: 4fd85fd2373501b7386e93a5ce4a549d7c4e64e3
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=4fd85fd2373501b7386e93a5ce4a549d7c4e64e3

Changed files:
  drivers/net/wireless/mediatek/mt76/mt7996/mcu.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=4fd85fd2373501b7386e93a5ce4a549d7c4e64e3

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

The original Linux kernel CVE announcement for CVE-2026-68308 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-68308

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:H
  The Best / paranoid CVSS vector: AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
  The Best / paranoid CVSS score: 5.3

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).