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

From: Greg Kroah-Hartman <[email protected]>

Description
===========

In the Linux kernel, the following vulnerability has been resolved:

ieee802154: admin-gate legacy LLSEC dump operations

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).

The Linux kernel CVE team has assigned CVE-2026-72049 to this issue.


Affected and fixed versions
===========================

	Issue introduced in 3.16 with commit 3e9c156e2c210ab67b12b1b692983a6b97c19d3f and fixed in 5.10.261 with commit 3465035ba18b1ed50f8d201897d14135d20532b0
	Issue introduced in 3.16 with commit 3e9c156e2c210ab67b12b1b692983a6b97c19d3f and fixed in 5.15.212 with commit dffe745760f38fac0b8288e0dc4759b23d9888ff
	Issue introduced in 3.16 with commit 3e9c156e2c210ab67b12b1b692983a6b97c19d3f and fixed in 6.1.178 with commit e84708ef7521f3bffc85a449954042018abbd60e
	Issue introduced in 3.16 with commit 3e9c156e2c210ab67b12b1b692983a6b97c19d3f and fixed in 6.6.145 with commit 5abe94a205539d27945cda3ba43fdcfe295cf2c8
	Issue introduced in 3.16 with commit 3e9c156e2c210ab67b12b1b692983a6b97c19d3f and fixed in 6.12.97 with commit 09fd25cd8cd80a6b3edef04e53a7324d06ac2180
	Issue introduced in 3.16 with commit 3e9c156e2c210ab67b12b1b692983a6b97c19d3f and fixed in 6.18.40 with commit 1905ebabe638c946aced00c4bb664da26cac56d5
	Issue introduced in 3.16 with commit 3e9c156e2c210ab67b12b1b692983a6b97c19d3f and fixed in 7.1.5 with commit 6383248058956f2a52d720b1e9f8921099cdae04
	Issue introduced in 3.16 with commit 3e9c156e2c210ab67b12b1b692983a6b97c19d3f and fixed in 7.2-rc1 with commit 9c1e0b6d49471a712511d23fc9d06901561135e8

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2026-72049
will be updated if fixes are backported, please check that for the most
up to date information about this issue.


Affected files
==============

The file(s) affected by this issue are:
	net/ieee802154/ieee802154.h
	net/ieee802154/netlink.c


Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/3465035ba18b1ed50f8d201897d14135d20532b0
	https://git.kernel.org/stable/c/dffe745760f38fac0b8288e0dc4759b23d9888ff
	https://git.kernel.org/stable/c/e84708ef7521f3bffc85a449954042018abbd60e
	https://git.kernel.org/stable/c/5abe94a205539d27945cda3ba43fdcfe295cf2c8
	https://git.kernel.org/stable/c/09fd25cd8cd80a6b3edef04e53a7324d06ac2180
	https://git.kernel.org/stable/c/1905ebabe638c946aced00c4bb664da26cac56d5
	https://git.kernel.org/stable/c/6383248058956f2a52d720b1e9f8921099cdae04
	https://git.kernel.org/stable/c/9c1e0b6d49471a712511d23fc9d06901561135e8