[CVE-2026-68404][MODERATE 7.0] wifi: cfg80211: use wiphy work for socket owner autodisconnect [ Upstream

[CVE-2026-68404][MODERATE 7.0] wifi: cfg80211: use wiphy work for socket owner autodisconnect [ Upstream

[AL-KERNEL]

CVE: CVE-2026-68404
Priority: MODERATE 7.0
AL-KERNEL base severity: MODERATE
KPANIC flag: YES
Patch: wifi: cfg80211: use wiphy work for socket owner autodisconnect [ Upstream
Commit: 6d6123fef5a4af175cc6b6b12a03dd0f3c240b79
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=6d6123fef5a4af175cc6b6b12a03dd0f3c240b79
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-68404
Analysis date: Mon, 10 Aug 2026 17:21:29 -0400
ActionableScore: 5
ActionableScore lower bound: 4
Actionable bucket: Actionable Moderate at minimum
Manual review required: YES

Summary:
A race between nl80211 socket owner release and cfg80211 wireless device teardown can queue autodisconnect work after cancellation, creating a stale embedded work item that may run after `wireless_dev` teardown and cause at least local kernel DoS with possible UAF impact.

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

The original Linux kernel CVE announcement for CVE-2026-68404 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-68404

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 7.0
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-2026-68404	MODERATE	CHECK WITH IMPACT FROM ORIG NN LOW	Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H';CWE-362;*CWE-416;CWE-667;*CWE-664;Other CVSS 'AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H';BEST CVSS score: '7';DESCR 'cfg80211 has a race between NETLINK_URELEASE socket owner autodisconnect and wireless device teardown. A notifier can observe a connection owner socket and queue wdev disconnect_wk after NETDEV_GOING_DOWN has already cancelled the old work item, while later unregister removes the wdev from the list and waits for RCU readers but does not drain work already queued by such a reader. Because the work item is embedded in struct wireless_dev and the callback derives wdev from that work item, this is a use after free candidate rather than a simple warning. For the CVSS the PR:L is used for the paranoid score because a local process that owns or can influence an nl80211 connection socket may race socket release against wireless device teardown, while full host root is not necessarily the only practical actor in delegated network management setups. The issue is not directly network reachable and packet traffic alone is not the trigger. Impact is at least local denial of service via kernel crash, and in the worst case may allow confidentiality or integrity impact due to kernel use after free behavior.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Actionable Moderate at minimum (with actual score 5)	YES	REMOTE LOCK INIT SIMPLEFIX HARDWARE KPANIC 	NO	NO	checked

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ACTIONABLESCORE ANALYSIS
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ActionableScore=5
ActionableScoreLower=4

## 1. ActionableScore

* Conservative score: 4
* Paranoid score: 5
* Final recommended bucket: **Actionable Moderate at minimum**::

## 2. Signal breakdown

Conservative signals:

* Local trigger context: +1. The issue is triggered through local nl80211 socket ownership and device teardown paths, not by remote WiFi traffic alone.
* Memory corruption, weak race-UAF candidate: +1. The queued work item is embedded in `struct wireless_dev`, and a notifier can queue it after prior cancellation while teardown proceeds.
* Real lifetime corruption: +1. This is an async workqueue lifetime mismatch against `wireless_dev` unregister and RCU teardown.
* Reliable kernel crash / strong DoS: +1. A stale autodisconnect work callback after device teardown can plausibly dereference invalid object state and crash the kernel.
* Hard or unreliable race / special timing required: -1. The bug requires a timing window between `NETLINK_URELEASE`, `NETDEV_GOING_DOWN`, cancellation, RCU list removal, and work execution.
* Requires privileged network management in typical deployments: -1. Directly creating the connection-owner state and racing device down or unregister commonly involves CAP_NET_ADMIN or a privileged network manager, but delegated network management can reduce the practical privilege boundary.

Paranoid additions / interpretation:

* Weak LPE concern: +1. The stale work callback executes later in kernel context and uses an object obtained from an embedded work item, so manual review should not auto-close it as DoS-only.
* Race-UAF cap applied. Because there is no demonstrated attacker-controlled reclaim, write-after-free, type confusion, refcount takeover, or arbitrary write, the paranoid score is capped at 5.

## 3. Reachability analysis

A local actor able to own or influence an nl80211 connection socket can participate in the `NETLINK_URELEASE` path. Reliable triggering also needs a concurrent wireless-device down or unregister path, which is normally controlled by privileged network-management code. In ordinary deployments this is not remotely reachable and incoming WiFi packets alone are not the trigger.

Namespaces and containers matter because CAP_NET_ADMIN may be delegated inside network namespaces or to reduced-privilege service accounts. Such actors are not always equivalent to full host root, so the paranoid interpretation treats this as a meaningful local boundary issue rather than pure PR:H administration-only behavior.

The affected subsystem is common on WiFi-capable systems, but not universal on servers. Call-site confidence: high, because the patch shows the notifier queue site, the teardown cancellation sites, and the callback conversion to `wiphy_work`.

## 4. Severity interpretation

This behaves stronger than an ordinary Moderate cleanup bug because it is a real async lifetime race around an embedded work item and object teardown. The realistic impact is local DoS through a kernel crash. The theoretical risk is higher because stale work execution after object teardown is a UAF-class pattern, but the patch does not show a controlled reclaim or write primitive. Therefore this is best treated as Actionable Moderate at minimum, not auto-closed, with weak Important-candidate concern only after manual review.

## 5. One-sentence report phrase

A race between nl80211 socket owner release and cfg80211 wireless device teardown can queue autodisconnect work after cancellation, creating a stale embedded work item that may run after `wireless_dev` teardown and cause at least local kernel DoS with possible UAF impact.

## 6. Manual review recommendation

MANUAL CHECK REQUIRED

Reason: this is a race-dependent lifetime bug involving queued kernel work and object teardown. The demonstrated impact is likely DoS, but the UAF-shaped callback path is significant enough to require manual review before downgrading or auto-closing.

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

Patch: wifi: cfg80211: use wiphy work for socket owner autodisconnect [ Upstream
Commit: 6d6123fef5a4af175cc6b6b12a03dd0f3c240b79
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=6d6123fef5a4af175cc6b6b12a03dd0f3c240b79

Changed files:
  include/net/cfg80211.h
  net/wireless/core.c
  net/wireless/core.h
  net/wireless/nl80211.c
  net/wireless/sme.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=6d6123fef5a4af175cc6b6b12a03dd0f3c240b79

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

The original Linux kernel CVE announcement for CVE-2026-68404 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-68404

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:L/UI:N/S:U/C:N/I:N/A:H
  The Best / paranoid CVSS vector: AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
  The Best / paranoid CVSS score: 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: 4
  Paranoid ActionableScore: 5

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: YES
Published priority for this report (same as in Subject): MODERATE 7.0

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).