| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| The Bluetooth LE host queues received L2CAP connection-oriented channel (CoC) data for deferred processing through a struct k_work embedded in the channel object (le_chan->rx_work, handler l2cap_rx_process()) whenever the channel uses a dynamic PSM (0x0080-0x00FF). Channel teardown in l2cap_chan_destroy() in subsys/bluetooth/host/l2cap.c cancels the retransmission-timeout work and drains the RX FIFO, but never cancels rx_work. Because that work item was submitted to the system workqueue while HCI receive processing runs on the dedicated Bluetooth RX workqueue (CONFIG_BT_RECV_WORKQ_BT, the default), a queued rx_work item can outlive the channel it points into.
A remote, unauthenticated peer with an established CoC channel triggers this by sending a data K-frame immediately followed by an L2CAP Disconnect Request. The K-frame submits rx_work to the system workqueue; because both workqueue threads are cooperative and the Bluetooth RX workqueue runs at the higher priority (K_PRIO_COOP(CONFIG_BT_RX_PRIO) versus CONFIG_SYSTEM_WORKQUEUE_PRIORITY), the pending item cannot run before the following Disconnect Request is processed in le_disconn_req() -> l2cap_chan_del() -> l2cap_chan_destroy(). The stack then invokes the released() callback, which the API documents as meaning the stack has dropped all references and the application may free the channel memory.
The application therefore frees or re-accepts into an object that the system workqueue still holds in its pending list. If the memory is freed and reallocated, the workqueue later dereferences a list node and a handler function pointer read from reused memory; if the object is re-used for a later connection, l2cap_chan_add() calls k_work_init() on a still-enqueued work item, corrupting the workqueue's pending list so that unrelated work items are dropped or the queue spins on a looped list. A related variant lets l2cap_rx_process() run concurrently with teardown, racing the net_buf unref of le_chan->_sdu and the clearing of chan->conn.
The fix routes the channel RX work to the Bluetooth workqueue - the same context in which every teardown path runs - and adds an explicit k_work_cancel() of le_chan->rx_work in l2cap_chan_destroy(), so no reference to the channel survives the released() callback. Configurations without CONFIG_BT_L2CAP_DYNAMIC_CHANNEL, or that only use SIG-assigned PSMs (EATT 0x0027, OTS 0x0025) which take the inline receive path, are not affected. |
| Improper resolution of path equivalence in Visual Studio Code allows an unauthorized attacker to bypass a security feature locally. |
| Use after free in Windows Bind Filter Driver allows an authorized attacker to elevate privileges locally. |
| Double free in Microsoft Office Outlook allows an unauthorized attacker to execute code over a network. |
| Use after free in Windows Win32 Kernel Subsystem allows an authorized attacker to elevate privileges locally. |
| Double free in Windows Hyper-V allows an authorized attacker to elevate privileges locally. |
| Use after free in Windows Bluetooth Port Driver allows an unauthorized attacker to elevate privileges over an adjacent network. |
| During an upload, curl mishandles HTTP/2 `RST_STREAM` received from the server
(with reason `HTTP_1_1_REQUIRED` or `REFUSED_STREAM`) leading to a use after
free of a `struct Curl_easy` object. |
| Use after free in Windows Graphics Kernel allows an authorized attacker to elevate privileges locally. |
| Use after free in Windows Installer allows an authorized attacker to elevate privileges locally. |
| libIEC61850 is an open-source implementation of IEC 61850 client and server protocols including MMS, GOOSE, Sampled Values, and R-Session. From 1.6.1 until 1.6.2, a successful MMS ObtainFile operation closes MmsObtainFileTask::fileHandle but leaves the stale non-NULL value in a task marked MMS_FILE_UPLOAD_STATE_NOT_USED. If a later ObtainFile request reuses that task and destination creation fails, MMS_FILE_UPLOAD_STATE_SEND_OBTAIN_FILE_ERROR_DESTINATION cleanup closes the stale FILE object again. Servers with the MMS file service and ObtainFile enabled can therefore be crashed remotely by the success-then-failure request sequence. This issue is fixed in version 1.6.2. |
| Use after free in Microsoft Office Excel allows an unauthorized attacker to execute code over a network. |
| Use after free in Windows Kernel allows an authorized attacker to elevate privileges locally. |
| Use after free in Windows Storage Spaces Controller allows an authorized attacker to elevate privileges locally. |
| Use after free in Windows Failover Cluster allows an unauthorized attacker to execute code over a network. |
| Use after free in Windows Broadcast DVR User Service allows an authorized attacker to elevate privileges locally. |
| Use after free in Windows Broadcast DVR User Service allows an authorized attacker to elevate privileges locally. |
| In the Linux kernel, the following vulnerability has been resolved:
ext4: fix use-after-free in update_super_work when racing with umount
Commit b98535d09179 ("ext4: fix bug_on in start_this_handle during umount
filesystem") moved ext4_unregister_sysfs() before flushing s_sb_upd_work
to prevent new error work from being queued via /proc/fs/ext4/xx/mb_groups
reads during unmount. However, this introduced a use-after-free because
update_super_work calls ext4_notify_error_sysfs() -> sysfs_notify() which
accesses the kobject's kernfs_node after it has been freed by kobject_del()
in ext4_unregister_sysfs():
update_super_work ext4_put_super
----------------- --------------
ext4_unregister_sysfs(sb)
kobject_del(&sbi->s_kobj)
__kobject_del()
sysfs_remove_dir()
kobj->sd = NULL
sysfs_put(sd)
kernfs_put() // RCU free
ext4_notify_error_sysfs(sbi)
sysfs_notify(&sbi->s_kobj)
kn = kobj->sd // stale pointer
kernfs_get(kn) // UAF on freed kernfs_node
ext4_journal_destroy()
flush_work(&sbi->s_sb_upd_work)
Instead of reordering the teardown sequence, fix this by making
ext4_notify_error_sysfs() detect that sysfs has already been torn down
by checking s_kobj.state_in_sysfs, and skipping the sysfs_notify() call
in that case. A dedicated mutex (s_error_notify_mutex) serializes
ext4_notify_error_sysfs() against kobject_del() in ext4_unregister_sysfs()
to prevent TOCTOU races where the kobject could be deleted between the
state_in_sysfs check and the sysfs_notify() call. |
| In the Linux kernel, the following vulnerability has been resolved:
ACPI: EC: clean up handlers on probe failure in acpi_ec_setup()
When ec_install_handlers() returns -EPROBE_DEFER on reduced-hardware
platforms, it has already started the EC and installed the address
space handler with the struct acpi_ec pointer as handler context.
However, acpi_ec_setup() propagates the error without any cleanup.
The caller acpi_ec_add() then frees the struct acpi_ec for non-boot
instances, leaving a dangling handler context in ACPICA.
Any subsequent AML evaluation that accesses an EC OpRegion field
dispatches into acpi_ec_space_handler() with the freed pointer,
causing a use-after-free:
BUG: KASAN: slab-use-after-free in mutex_lock (kernel/locking/mutex.c:289)
Write of size 8 at addr ffff88800721de38 by task init/1
Call Trace:
<TASK>
mutex_lock (kernel/locking/mutex.c:289)
acpi_ec_space_handler (drivers/acpi/ec.c:1362)
acpi_ev_address_space_dispatch (drivers/acpi/acpica/evregion.c:293)
acpi_ex_access_region (drivers/acpi/acpica/exfldio.c:246)
acpi_ex_field_datum_io (drivers/acpi/acpica/exfldio.c:509)
acpi_ex_extract_from_field (drivers/acpi/acpica/exfldio.c:700)
acpi_ex_read_data_from_field (drivers/acpi/acpica/exfield.c:327)
acpi_ex_resolve_node_to_value (drivers/acpi/acpica/exresolv.c:392)
</TASK>
Allocated by task 1:
acpi_ec_alloc (drivers/acpi/ec.c:1424)
acpi_ec_add (drivers/acpi/ec.c:1692)
Freed by task 1:
kfree (mm/slub.c:6876)
acpi_ec_add (drivers/acpi/ec.c:1751)
The bug triggers on reduced-hardware EC platforms (ec->gpe < 0)
when the GPIO IRQ provider defers probing. Once the stale handler
exists, any unprivileged sysfs read that causes AML to touch an
EC OpRegion (battery, thermal, backlight) exercises the dangling
pointer.
Fix this by calling ec_remove_handlers() in the error path of
acpi_ec_setup() before clearing first_ec. ec_remove_handlers()
checks each EC_FLAGS_* bit before acting, so it is safe to call
regardless of how far ec_install_handlers() progressed:
-ENODEV (handler not installed): only calls acpi_ec_stop()
-EPROBE_DEFER (handler installed): removes handler, stops EC |
| In the Linux kernel, the following vulnerability has been resolved:
net: bonding: fix use-after-free in bond_xmit_broadcast()
bond_xmit_broadcast() reuses the original skb for the last slave
(determined by bond_is_last_slave()) and clones it for others.
Concurrent slave enslave/release can mutate the slave list during
RCU-protected iteration, changing which slave is "last" mid-loop.
This causes the original skb to be double-consumed (double-freed).
Replace the racy bond_is_last_slave() check with a simple index
comparison (i + 1 == slaves_count) against the pre-snapshot slave
count taken via READ_ONCE() before the loop. This preserves the
zero-copy optimization for the last slave while making the "last"
determination stable against concurrent list mutations.
The UAF can trigger the following crash:
==================================================================
BUG: KASAN: slab-use-after-free in skb_clone
Read of size 8 at addr ffff888100ef8d40 by task exploit/147
CPU: 1 UID: 0 PID: 147 Comm: exploit Not tainted 7.0.0-rc3+ #4 PREEMPTLAZY
Call Trace:
<TASK>
dump_stack_lvl (lib/dump_stack.c:123)
print_report (mm/kasan/report.c:379 mm/kasan/report.c:482)
kasan_report (mm/kasan/report.c:597)
skb_clone (include/linux/skbuff.h:1724 include/linux/skbuff.h:1792 include/linux/skbuff.h:3396 net/core/skbuff.c:2108)
bond_xmit_broadcast (drivers/net/bonding/bond_main.c:5334)
bond_start_xmit (drivers/net/bonding/bond_main.c:5567 drivers/net/bonding/bond_main.c:5593)
dev_hard_start_xmit (include/linux/netdevice.h:5325 include/linux/netdevice.h:5334 net/core/dev.c:3871 net/core/dev.c:3887)
__dev_queue_xmit (include/linux/netdevice.h:3601 net/core/dev.c:4838)
ip6_finish_output2 (include/net/neighbour.h:540 include/net/neighbour.h:554 net/ipv6/ip6_output.c:136)
ip6_finish_output (net/ipv6/ip6_output.c:208 net/ipv6/ip6_output.c:219)
ip6_output (net/ipv6/ip6_output.c:250)
ip6_send_skb (net/ipv6/ip6_output.c:1985)
udp_v6_send_skb (net/ipv6/udp.c:1442)
udpv6_sendmsg (net/ipv6/udp.c:1733)
__sys_sendto (net/socket.c:730 net/socket.c:742 net/socket.c:2206)
__x64_sys_sendto (net/socket.c:2209)
do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
</TASK>
Allocated by task 147:
Freed by task 147:
The buggy address belongs to the object at ffff888100ef8c80
which belongs to the cache skbuff_head_cache of size 224
The buggy address is located 192 bytes inside of
freed 224-byte region [ffff888100ef8c80, ffff888100ef8d60)
Memory state around the buggy address:
ffff888100ef8c00: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc
ffff888100ef8c80: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888100ef8d00: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
^
ffff888100ef8d80: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb
ffff888100ef8e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
================================================================== |