Linux: >> Linux Kernel >> 6.18.11 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
scsi: target: configfs: Bound snprintf() return in tg_pt_gp_members_show()
target_tg_pt_gp_members_show() formats LUN paths with snprintf() into a
256-byte stack buffer, then will memcpy() cur_len bytes from that
buffer. snprintf() returns the length the output would have had, which
can exceed the buffer size when the fabric WWN is long because iSCSI IQN
names can be up to 223 bytes. The check at the memcpy() site only
guards the destination page write, not the source read, so memcpy() will
read past the stack buffer and copy adjacent stack contents to the sysfs
reader, which when CONFIG_FORTIFY_SOURCE is enabled, fortify_panic()
will be triggered.
Commit 27e06650a5ea ("scsi: target: target_core_configfs: Add length
check to avoid buffer overflow") added the same bound to the
target_lu_gp_members_show() but the tg_pt_gp variant was missed so
resolve that here.
CVSS Score
7.1
EPSS Score
0.001
Published
2026-05-28
In the Linux kernel, the following vulnerability has been resolved:
fanotify: fix false positive on permission events
fsnotify_get_mark_safe() may return false for a mark on an unrelated group,
which results in bypassing the permission check.
Fix by skipping over detached marks that are not in the current group.
CVSS Score
7.1
EPSS Score
0.001
Published
2026-05-28
In the Linux kernel, the following vulnerability has been resolved:
usb: usblp: fix heap leak in IEEE 1284 device ID via short response
usblp_ctrl_msg() collapses the usb_control_msg() return value to
0/-errno, discarding the actual number of bytes transferred. A broken
printer can complete the GET_DEVICE_ID control transfer short and the
driver has no way to know.
usblp_cache_device_id_string() reads the 2-byte big-endian length prefix
from the response and trusts it (clamped only to the buffer bounds).
The buffer is kmalloc(1024) at probe time. A device that sends exactly
two bytes (e.g. 0x03 0xFF, claiming a 1023-byte ID) leaves
device_id_string[2..1022] holding stale kmalloc heap.
That stale data is then exposed:
- via the ieee1284_id sysfs attribute (sprintf("%s", buf+2), truncated
at the first NUL in the stale heap), and
- via the IOCNR_GET_DEVICE_ID ioctl, which copy_to_user()s the full
claimed length regardless of NULs, up to 1021 bytes of uninitialized
heap, with the leak size chosen by the device.
Fix this up by just zapping the buffer with zeros before each request
sent to the device.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-05-28
In the Linux kernel, the following vulnerability has been resolved:
wifi: mac80211: drop stray 'static' from fast-RX rx_result
ieee80211_invoke_fast_rx() is documented as safe for parallel RX, but
its per-invocation rx_result is declared static. Concurrent callers then
share one instance and can overwrite each other's result between
ieee80211_rx_mesh_data() and the switch on res.
That can make a packet that was queued or consumed by
ieee80211_rx_mesh_data() fall through into ieee80211_rx_8023(), or make
a packet that should continue return as queued.
Make res an automatic variable so each invocation keeps its own result.
CVSS Score
8.8
EPSS Score
0.002
Published
2026-05-28
In the Linux kernel, the following vulnerability has been resolved:
8021q: delete cleared egress QoS mappings
vlan_dev_set_egress_priority() currently keeps cleared egress
priority mappings in the hash as tombstones. Repeated set/clear cycles
with distinct skb priorities therefore accumulate mapping nodes until
device teardown and leak memory.
Delete mappings when vlan_prio is cleared instead of keeping tombstones.
Now that the egress mapping lists are RCU protected, the node can be
unlinked safely and freed after a grace period.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-05-28
In the Linux kernel, the following vulnerability has been resolved:
nvmet-tcp: fix race between ICReq handling and queue teardown
nvmet_tcp_handle_icreq() updates queue->state after sending an
Initialization Connection Response (ICResp), but it does so without
serializing against target-side queue teardown.
If an NVMe/TCP host sends an Initialization Connection Request
(ICReq) and immediately closes the connection, target-side teardown
may start in softirq context before io_work drains the already
buffered ICReq. In that case, nvmet_tcp_schedule_release_queue()
sets queue->state to NVMET_TCP_Q_DISCONNECTING and drops the queue
reference under state_lock.
If io_work later processes that ICReq, nvmet_tcp_handle_icreq() can
still overwrite the state back to NVMET_TCP_Q_LIVE. That defeats the
DISCONNECTING-state guard in nvmet_tcp_schedule_release_queue() and
allows a later socket state change to re-enter teardown and issue a
second kref_put() on an already released queue.
The ICResp send failure path has the same problem. If teardown has
already moved the queue to DISCONNECTING, a send error can still
overwrite the state with NVMET_TCP_Q_FAILED, again reopening the
window for a second teardown path to drop the queue reference.
Fix this by serializing both post-send state transitions with
state_lock and bailing out if teardown has already started.
Use -ESHUTDOWN as an internal sentinel for that bail-out path rather
than propagating it as a transport error like -ECONNRESET. Keep
nvmet_tcp_socket_error() setting rcv_state to NVMET_TCP_RECV_ERR before
honoring that sentinel so receive-side parsing stays quiesced until the
existing release path completes.
CVSS Score
9.8
EPSS Score
0.004
Published
2026-05-28
In the Linux kernel, the following vulnerability has been resolved:
wifi: mt76: mt7921: fix a potential clc buffer length underflow
The buf_len is used to limit the iterations for retrieving the country
power setting and may underflow under certain conditions due to changes
in the power table in CLC.
This underflow leads to an almost infinite loop or an invalid power
setting resulting in driver initialization failure.
CVSS Score
7.8
EPSS Score
0.001
Published
2026-05-28
In the Linux kernel, the following vulnerability has been resolved:
mptcp: pm: ADD_ADDR rtx: fix potential data-race
This mptcp_pm_add_timer() helper is executed as a timer callback in
softirq context. To avoid any data races, the socket lock needs to be
held with bh_lock_sock().
If the socket is in use, retry again soon after, similar to what is done
with the keepalive timer.
CVSS Score
9.8
EPSS Score
0.004
Published
2026-05-28
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: hci_event: Fix OOB read and infinite loop in hci_le_create_big_complete_evt
hci_le_create_big_complete_evt() iterates over BT_BOUND connections for
a BIG handle using a while loop, accessing ev->bis_handle[i++] on each
iteration. However, there is no check that i stays within ev->num_bis
before the array access.
When a controller sends a LE_Create_BIG_Complete event with fewer
bis_handle entries than there are BT_BOUND connections for that BIG,
or with num_bis=0, the loop reads beyond the valid bis_handle[] flex
array into adjacent heap memory. Since the out-of-bounds values
typically exceed HCI_CONN_HANDLE_MAX (0x0EFF), hci_conn_set_handle()
rejects them and the connection remains in BT_BOUND state. The same
connection is then found again by hci_conn_hash_lookup_big_state(),
creating an infinite loop with hci_dev_lock held.
Fix this by terminating the BIG if in case not all BIS could be setup
properly.
CVSS Score
8.1
EPSS Score
0.003
Published
2026-05-28
In the Linux kernel, the following vulnerability has been resolved:
smb: client: use kzalloc to zero-initialize security descriptor buffer
Commit 62e7dd0a39c2d ("smb: common: change the data type of num_aces
to le16") split struct smb_acl's __le32 num_aces field into __le16
num_aces and __le16 reserved. The reserved field corresponds to Sbz2
in the MS-DTYP ACL wire format, which must be zero [1].
When building an ACL descriptor in build_sec_desc(), we are using a
kmalloc()'ed descriptor buffer and writing the fields explicitly using
le16() writes now. This never writes to the 2 byte reserved field,
leaving it as uninitialized heap data.
When the reserved field happens to contain non-zero slab garbage,
Samba rejects the security descriptor with "ndr_pull_security_descriptor
failed: Range Error", causing chmod to fail with EINVAL.
Change kmalloc() to kzalloc() to ensure the entire buffer is
zero-initialized.
[1] https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-dtyp/20233ed8-a6c6-4097-aafa-dd545ed24428
CVSS Score
5.5
EPSS Score
0.001
Published
2026-05-28