[CVE-2026-68472][MODERATE 7.0] wifi: cfg80211: validate EHT MLE before MLD ID read

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

CVE: CVE-2026-68472
Priority: MODERATE 7.0
AL-KERNEL base severity: MODERATE
KPANIC flag: NO
Patch: wifi: cfg80211: validate EHT MLE before MLD ID read
Commit: 584657c5fc58d7a840623a2fa06331c9661dd0f1
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=584657c5fc58d7a840623a2fa06331c9661dd0f1
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-68472
Analysis date: Sat, 15 Aug 2026 16:20:13 -0400
ActionableScore: 5
ActionableScore lower bound: 4
Actionable bucket: Actionable Moderate at minimum
Manual review required: YES

Summary:
A malicious Wi-Fi AP in radio range can send a short EHT MLE inside an MBSSID frame, causing cfg80211 to read past the IE boundary before validating the MLE type and size, with likely impact limited to adjacent-network DoS and limited OOB-read risk.

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ABOUT THIS REPORT
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The original Linux kernel CVE announcement for CVE-2026-68472 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-68472

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-2026-68472	MODERATE	CHECK WITH IMPACT FROM ORIG NN MODERATE	Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H';CWE-125;*CWE-20;CWE-130;Other CVSS 'AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L';BEST CVSS score: '7.1';DESCR 'A short EHT MLE in an MBSSID beacon can reach cfg80211_gen_new_ie and cause ieee80211_mle_get_mld_id to read past the IE boundary before the MLE type and size are validated. A malicious Wi-Fi AP in radio range can trigger this through crafted management frames during scan or BSS discovery. For the CVSS the PR:N because no local account on the victim is required and the attacker only needs adjacent wireless reachability to transmit the malformed frame. The issue is adjacent-network reachable rather than Internet reachable. Impact is at least a parser out-of-bounds read and possible denial of service. For the paranoid score, choose the highest still-defensible interpretation supported by the bug class and patch context, with preference for manual-review sensitivity over autoclosed false negatives.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Actionable Moderate at minimum (with actual score 5)	YES	REMOTE  DECREASED_TO_MODERATEREG_BASED_ON_FALSEPOSCHECKOFKP	YES	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:

* **Remote reachable / network-triggerable: +2**
  Trigger is a crafted Wi-Fi management frame from a malicious AP in radio range. This is adjacent-network reachable, not Internet reachable, but it is still externally triggerable without local code execution on the victim.

* **Broad/default/common subsystem exposure: +1**
  cfg80211 scan and BSS parsing are common Wi-Fi client paths on systems with wireless hardware.

* **Availability impact realistic: +1**
  The patch prevents an out-of-bounds read before parsing internal MLE fields. A crash is plausible if the read crosses an allocation boundary or hits hardened/debug configurations.

Paranoid additional signals:

* **Confidentiality impact plausible: +1**
  The primitive is read-only OOB. No disclosure path is shown, so this is not strong C impact, but a limited kernel parser OOB read justifies paranoid C:L review.

Not awarded:

* **Generic memory corruption: +0**
  This is not UAF, OOB write, double-free, type confusion, or arbitrary write.

* **Privilege escalation plausible: +0**
  No write primitive, reclaim primitive, callback control, refcount manipulation, or object confusion is shown.

* **Integrity impact plausible: +0**
  The patch shows validation before read, not attacker-controlled modification.

## 3. Reachability analysis

A malicious AP or attacker able to transmit crafted Wi-Fi beacon or probe-response style management frames in radio range can trigger the affected parsing path during scan or BSS discovery. No local account on the victim is required.

Namespaces and containers do not materially reduce the attack requirement because the trigger is external wireless adjacency, not a local syscall or netlink interface. The path is relevant only on systems with Wi-Fi and cfg80211 handling EHT MBSSID / MLO elements. It is not Internet-reachable and requires physical or RF proximity.

Call-site confidence: **high**, because the commit message gives the exact chain through `cfg80211_inform_bss_frame_data()`, `cfg80211_parse_mbssid_data()`, `cfg80211_gen_new_ie()`, and `ieee80211_mle_get_mld_id()`.

## 4. Severity interpretation

This behaves like an **actionable Moderate** issue rather than ordinary Low because it is externally triggerable from adjacent Wi-Fi range and reaches a kernel parser OOB read. It is not a strong Important candidate on the available evidence because the patch supports only an out-of-bounds read, not OOB write, UAF, type confusion, arbitrary write, or demonstrated privilege escalation.

The paranoid score is higher because adjacent-network kernel parser bugs can be under-triaged when the visible symptom is only a bounds read, especially if crashability depends on allocator layout or hardening.

## 5. One-sentence report phrase

A malicious Wi-Fi AP in radio range can send a short EHT MLE inside an MBSSID frame, causing cfg80211 to read past the IE boundary before validating the MLE type and size, with likely impact limited to adjacent-network DoS and limited OOB-read risk.

## 6. Manual review recommendation

**MANUAL CHECK REQUIRED**

Reason: adjacent-network reachable kernel parser OOB read. It should not be auto-closed without checking whether the OOB read can reliably crash, disclose adjacent heap data, or be reached in common Wi-Fi client scanning configurations.

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

Patch: wifi: cfg80211: validate EHT MLE before MLD ID read
Commit: 584657c5fc58d7a840623a2fa06331c9661dd0f1
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=584657c5fc58d7a840623a2fa06331c9661dd0f1

Commit description:

cfg80211_gen_new_ie() copies ML probe response elements from
the parent frame when the parent EHT multi-link element has an
MLD ID matching the nontransmitted BSSID index.

The code only checked that the extension element had more than
one byte before calling ieee80211_mle_get_mld_id(). That helper
assumes a BASIC MLE with enough common info and documents that
callers must first use ieee80211_mle_type_ok().

Attack chain:
malicious AP sends a short EHT MLE in an MBSSID beacon.
cfg80211_inform_bss_frame_data() stores the copied IE buffer.
cfg80211_parse_mbssid_data() builds the nontransmitted BSS IE.
cfg80211_gen_new_ie() sees the EHT MLE in the parent frame.
ieee80211_mle_get_mld_id() then reads past the IE boundary.

Validate the MLE type and size before reading the MLD ID. This
matches the contract required by the MLE helper and rejects the
short element before any internal MLE fields are accessed.

Cc: stable@vger.kernel.org
Fixes: 61dcfa8 ("wifi: cfg80211: copy multi-link element from the multi-link probe request's frame body to the generated elements")
Signed-off-by: Haofeng Li <lihaofeng@kylinos.cn>
Link: https://patch.msgid.link/20260701093327.2680709-1-lihaofeng@kylinos.cn
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Changed files:
  net/wireless/scan.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=584657c5fc58d7a840623a2fa06331c9661dd0f1

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

The original Linux kernel CVE announcement for CVE-2026-68472 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-68472

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:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
  The Best / paranoid CVSS vector: AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H
  The Best / paranoid CVSS score: 7.1

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: NO
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).