[CVE-2026-72049][IMPORTANT] ieee802154: admin-gate legacy LLSEC dump operations

[CVE-2026-72049][IMPORTANT] ieee802154: admin-gate legacy LLSEC dump operations

[AL-KERNEL]

CVE: CVE-2026-72049
Priority: IMPORTANT
AL-KERNEL base severity: IMPORTANT
KPANIC flag: YES
Patch: ieee802154: admin-gate legacy LLSEC dump operations
Commit: 3465035ba18b1ed50f8d201897d14135d20532b0
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=3465035ba18b1ed50f8d201897d14135d20532b0
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-72049
Analysis date: Sat, 15 Aug 2026 10:24:20 -0400
ActionableScore: 7
ActionableScore lower bound: unknown
Actionable bucket: Strong Important candidate / Actionable Moderate at minimum
Manual review required: YES

Summary:
Legacy IEEE802154_NL LLSEC dump operations lacked GENL_ADMIN_PERM, allowing an unprivileged local user to disclose raw AES-128 LLSEC keys and compromise 802.15.4 link confidentiality and authenticity.

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

The original Linux kernel CVE announcement for CVE-2026-72049 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-72049

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: IMPORTANT
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-2026-72049	IMPORTANT	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:C/C:H/I:H/A:N';CWE-862;*CWE-200;CWE-522;Other CVSS 'AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N';BEST CVSS score: '8.4';DESCR 'Legacy IEEE802154_NL LLSEC dump operations were not gated with GENL_ADMIN_PERM, so an unprivileged local user could query LLSEC_LIST_KEY and receive raw 16-byte AES-128 key material from an administrator configured WPAN interface. Disclosure of the LLSEC key compromises link confidentiality and authenticity because the same key is used by 802.15.4 LLSEC CCM* processing to protect and authenticate frames. For the CVSS the PR:L is selected because any local unprivileged user can reach the legacy generic netlink family without capabilities, while no remote network path is needed to trigger the kernel disclosure. Impact is primarily information disclosure with strong secondary integrity impact against the 802.15.4 link. Availability impact is not indicated by the patch context.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Strong Important candidate / Actionable Moderate at minimum (with actual score 7)	YES	LINUS  KPANIC INCREASED_TO_MODERATE_FROM_LOW_BASED_ON_GUESSCVSS KPANIC INCREASED_TO_HIGH_BASED_ON_ACTIONABLESCOREHIGHEREQTHAN6	NO	NO	checked

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

ActionableScore=7

## 1. ActionableScore

* Conservative score: 7
* Paranoid score: 7
* Final recommended bucket: **Strong Important candidate / Actionable Moderate at minimum**::

## 2. Signal breakdown

* Local unprivileged trigger: +1
  Any local uid that can open `AF_NETLINK / NETLINK_GENERIC` can query the legacy `IEEE802154_NL` family.

* Security-boundary bypass with practical sensitive-object access: +2
  LLSEC dump operations were intended to be admin-gated, as shown by the modern `nl802154` equivalent using `GENL_ADMIN_PERM`.

* Sensitive secret theft primitive: +2
  `LLSEC_LIST_KEY` exposes raw 16-byte AES-128 LLSEC key material from the kernel keytable.

* Practical exploit chain strongly implied: +1
  The chain is direct: unprivileged netlink dump -> raw LLSEC key disclosure -> compromise of 802.15.4 LLSEC traffic confidentiality and authenticity.

* Confidentiality impact plausible: +1
  The disclosed AES key protects link-layer encrypted traffic.

* Integrity impact plausible: +1
  The same LLSEC key is used for CCM* authentication, so key recovery can enable forged authenticated frames in the affected 802.15.4 domain.

* Rare / configuration-dependent subsystem: -1
  Requires IEEE 802.15.4 / WPAN LLSEC usage and an administrator-installed LLSEC key, which is not a broad default server exposure.

Total: 1 + 2 + 2 + 1 + 1 + 1 - 1 = 7

## 3. Reachability analysis

A local unprivileged user can trigger the issue if the system has the legacy IEEE802154 generic netlink family available and a WPAN interface with LLSEC keys installed. No network reachability to the Linux host is required. Namespaces may matter depending on whether the IEEE802154 netlink family and WPAN device are visible inside a container, but the core issue is that no capability check was applied to sensitive LLSEC dump operations. The path is not common on general-purpose systems, but it is realistic on embedded, IoT, industrial, or test systems using 802.15.4 LLSEC.

## 4. Severity interpretation

This is not memory corruption and does not imply kernel code execution or DoS. It is a direct access-control failure that exposes cryptographic key material to an unprivileged local user. Because the leaked key can compromise both confidentiality and authenticity of 802.15.4 LLSEC traffic, this is stronger than an ordinary Moderate information disclosure and should be treated as an Important candidate or at least an actionable Moderate that should not be auto-closed.

## 5. One-sentence report phrase

Legacy IEEE802154_NL LLSEC dump operations lacked GENL_ADMIN_PERM, allowing an unprivileged local user to disclose raw AES-128 LLSEC keys and compromise 802.15.4 link confidentiality and authenticity.

## 6. Manual review recommendation

MANUAL CHECK REQUIRED

Reason: direct unprivileged disclosure of administrator-installed cryptographic keys is a practical security-boundary bypass with high confidentiality impact and meaningful secondary integrity impact, even though the affected subsystem is configuration-dependent.

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

Patch: ieee802154: admin-gate legacy LLSEC dump operations
Commit: 3465035ba18b1ed50f8d201897d14135d20532b0
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=3465035ba18b1ed50f8d201897d14135d20532b0

Commit description:

In net/ieee802154/netlink.c, the legacy IEEE802154_NL family ops table
builds the LLSEC dump entries (LLSEC_LIST_KEY, LLSEC_LIST_DEV,
LLSEC_LIST_DEVKEY, LLSEC_LIST_SECLEVEL) with IEEE802154_DUMP() which
sets no .flags, so generic netlink runs them ungated. The modern
nl802154 family admin-gates the equivalent reads via
NL802154_CMD_GET_SEC_KEY and friends with .flags = GENL_ADMIN_PERM.

Any local uid that can open AF_NETLINK / NETLINK_GENERIC can resolve
the "802.15.4 MAC" family and dump LLSEC_LIST_KEY on any wpan netdev
that has an LLSEC key installed; the dump handler writes the raw
16-byte AES-128 key bytes (IEEE802154_ATTR_LLSEC_KEY_BYTES, copied
verbatim from struct ieee802154_llsec_key.key) into the reply.
Recovering the AES key compromises 802.15.4 LLSEC link confidentiality
and authenticity, since LLSEC uses CCM* and the same key authenticates
and encrypts frames.

Impact: any local uid with no capabilities can read the raw 16-byte
AES-128 LLSEC key from the kernel keytable on any wpan netdev that has
an administrator-installed LLSEC key, by issuing an LLSEC_LIST_KEY
dump on the legacy IEEE802154_NL generic-netlink family.

Introduce IEEE802154_DUMP_PRIV() mirroring IEEE802154_DUMP() but
setting .flags = GENL_ADMIN_PERM, and use it for the four LLSEC dump
entries. LIST_PHY and LIST_IFACE retain IEEE802154_DUMP() because the
modern nl802154 family exposes their equivalents to unprivileged
readers by design (NL802154_CMD_GET_WPAN_PHY and
NL802154_CMD_GET_INTERFACE carry "can be retrieved by unprivileged
users" annotations).

Fixes: 3e9c156 ("ieee802154: add netlink interfaces for llsec")
Cc: stable@vger.kernel.org
Assisted-by: Claude:claude-opus-4-7
Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com>
Link: https://lore.kernel.org/20260520141640.1149513-2-michael.bommarito@gmail.com
Signed-off-by: Stefan Schmidt <stefan@datenfreihafen.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Changed files:
  net/ieee802154/netlink.c
  net/ieee802154/ieee802154.h

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=3465035ba18b1ed50f8d201897d14135d20532b0

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

The original Linux kernel CVE announcement for CVE-2026-72049 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-72049

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:L/PR:L/UI:N/S:U/C:H/I:H/A:N
  The Best / paranoid CVSS vector: AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N
  The Best / paranoid CVSS score: 8.4

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: unknown
  Paranoid ActionableScore: 7

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: IMPORTANT
KPANIC detected for this report: YES
Published priority for this report (same as in Subject): IMPORTANT

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).