| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
sunrpc: pin svc_xprt across the asynchronous TLS handshake callback
svc_tcp_handshake() stores the raw svc_xprt pointer in
tls_handshake_args.ta_data and submits the request through
tls_server_hello_x509(). The handshake core takes only
sock_hold(req->hr_sk); nothing references the embedding struct
svc_sock that svc_tcp_handshake_done() reaches via container_of().
Two close races leave the in-flight callback writing through a freed
svc_sock. svc_sock_free() calls tls_handshake_cancel() and discards
its return value: a false return means handshake_complete() has
already set HANDSHAKE_F_REQ_COMPLETED but hp_done() may not have
finished, yet svc_sock_free() proceeds to kfree(svsk). The
cancel-loser fall-through inside svc_tcp_handshake() itself produces
the same window: when wait_for_completion_interruptible_timeout()
returns <= 0 (timeout or signal) and tls_handshake_cancel() returns
false, the function does not drain, returns, and svc_handle_xprt()
calls svc_xprt_received(), which clears XPT_BUSY and can drop the
last reference. A concurrent close then runs svc_sock_free() while
svc_tcp_handshake_done() is still updating xpt_flags and walking
svsk->sk_handshake_done.
The corruption surfaces as set_bit/clear_bit RMW into the freed
xpt_flags slab slot and as complete_all() walking and writing the
freed wait_queue_head_t list embedded in sk_handshake_done -- a
slab-corruption primitive, not a benign read. The path is reachable
on any TLS-enabled NFS server whenever a connection close overlaps
the tlshd downcall delivery window; the interruptible wait means
signal delivery suffices, not just SVC_HANDSHAKE_TO expiry.
Take svc_xprt_get(xprt) immediately before tls_server_hello_x509()
so the in-flight callback owns its own reference. Release it on the
two edges where the callback is guaranteed not to fire -- submission
failure from tls_server_hello_x509() and a successful
tls_handshake_cancel() -- and at the tail of
svc_tcp_handshake_done() after complete_all().
[cel: rewrote commit message to describe the actual change] |
| In the Linux kernel, the following vulnerability has been resolved:
batman-adv: frag: free unfragmentable packet
The caller of batadv_frag_send_packet() assume that the skb provided to the
function are always consumed. But the pre-check for an empty payload or the
zero fragment size returned an error without any further actions.
A failed pre-check must use the same error handling code as the rest of the
function. |
| In the Linux kernel, the following vulnerability has been resolved:
batman-adv: bla: reacquire gw address after skb realloc
The pskb_may_pull() called by batadv_bla_is_backbone_gw() could reallocate
the buffer behind the skb. Variables which were pointing to the old buffer
need to be reassigned to avoid an use-after-free. |
| In the Linux kernel, the following vulnerability has been resolved:
mtd: slram: remove failed entries from the device list
register_device() links a new slram_mtdlist entry before allocating all
of the state needed by the entry. If a later allocation, memremap(), or
mtd_device_register() fails, the partially initialized entry remains on
the global list. A later cleanup can then dereference or free invalid
state from that failed entry.
Unwind the partially initialized entry and clear the list tail on each
failure path after the entry has been linked. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf,fork: wipe ->bpf_storage before bailouts that access it
Currently, copy_process() can bail out to free_task() before p->bpf_storage
has been initialized, with this call graph (shown here for the
!CONFIG_MEMCG case):
copy_process
dup_task_struct
arch_dup_task_struct
[copies the entire task_struct, including ->bpf_storage member]
[RLIMIT_NPROC check fails]
delayed_free_task
free_task
bpf_task_storage_free
rcu_dereference(task->bpf_storage)
bpf_local_storage_destroy
In this case, the nascent task's ->bpf_storage member that
bpf_local_storage_destroy() operates on is a plain copy of the parent's
->bpf_storage pointer, not a real initialized pointer.
This leads to badness (kernel hangs, UAF).
This is reachable as long as the process calling fork() has been inserted
into a task storage map. |
| In the Linux kernel, the following vulnerability has been resolved:
io_uring/bpf-ops: reject re-registration of an already-bound ops
io_install_bpf() only rejects a second registration on the ctx side
(ctx->bpf_ops) and sets the per-map back-pointer ops->priv
unconditionally. The struct_ops link path never advances a map past
BPF_STRUCT_OPS_STATE_READY, so the same io_uring_bpf_ops map can be
registered more than once, and bpf_io_reg() re-resolves the target ring
via fget(ops->ring_fd) on every call. A caller can therefore point the
same ring_fd at a different io_ring_ctx between two BPF_LINK_CREATE
calls.
The second registration passes the ctx->bpf_ops check (the new ctx has
none) and overwrites ops->priv, orphaning the first ctx. Teardown
(io_eject_bpf()/bpf_io_unreg()) only reaches a ctx through ops->priv, so
the orphaned ctx is never torn down: its ctx->loop_step keeps pointing
into the struct_ops trampoline, which is freed once the map is gone. A
later io_uring_enter() on the orphaned ring then calls the dangling
ctx->loop_step from io_run_loop() -- a use-after-free of freed
executable memory, reachable by a task with CAP_BPF + CAP_PERFMON.
Reject registration when ops->priv is already set, as hid_bpf_reg()
does for its struct_ops. |
| In the Linux kernel, the following vulnerability has been resolved:
can: bcm: defer rx_op deallocation to workqueue to fix thrtimer UAF
Commit f1b4e32aca08 ("can: bcm: use call_rcu() instead of costly
synchronize_rcu()") replaced synchronize_rcu() in bcm_delete_rx_op()
with call_rcu() and introduced the RX_NO_AUTOTIMER flag.
However, this flag check was omitted for thrtimer in the packet rx
fast-path. During BCM RX operation teardown, a concurrent RCU reader
(bcm_rx_handler) can race and re-arm thrtimer via
bcm_rx_update_and_send() after call_rcu() has been scheduled. Once
the RCU grace period elapses, bcm_op is freed. The subsequently
firing thrtimer then dereferences the deallocated op, causing a UAF.
Adding flag checks to the rx fast-path (bcm_rx_update_and_send) does not
fully close the TOCTOU race and introduces latency for every CAN frame.
Conversely, calling hrtimer_cancel() directly inside the RCU callback
(softirq context) is fatal as hrtimer_cancel() can sleep, triggering
a "scheduling while atomic" panic.
Resolve this by deferring the timer cancellation and memory free to a
dedicated unbound workqueue (bcm_wq). The RCU callback now queues a
work item to bcm_wq, which safely cancels both timers and deallocates
memory in sleepable process context. A dedicated workqueue is used to
prevent system-wide WQ saturation and is cleanly flushed/destroyed
on module unload to avoid rmmod page faults.
Since the deferred work can now outlive the calling context by an
unbounded amount, also take a reference on op->sk when it is assigned
and drop it only once the deferred work has cancelled both timers, so a
socket can no longer be freed out from under a still-armed timer whose
callback (bcm_send_to_user()) dereferences op->sk. |
| In the Linux kernel, the following vulnerability has been resolved:
xen/gntdev: fix error handling in ioctl
When gntdev_ioctl_map_grant_ref() fails to copy the operation result
back to userspace after successfully adding the mapping to the list,
the error path returns -EFAULT without releasing the reference
acquired by gntdev_alloc_map(). The mapping remains in priv->maps
with a refcount of 1, causing a memory leak and a dangling list
entry.
Additionally, gntdev_add_map() may modify map->index to avoid overlap
with existing mappings. Therefore, the index returned to userspace
must be obtained after gntdev_add_map() completes.
Fix this by holding the mutex across gntdev_add_map(), retrieving
the correct index, and copy_to_user(). If copy_to_user() fails,
remove the mapping from the list and release the reference while
still holding the lock.
Fix these issues by properly handling all error cases. |
| In the Linux kernel, the following vulnerability has been resolved:
i2c: mlxbf: Fix use-after-free in mlxbf_i2c_init_resource()
If devm_platform_get_and_ioremap_resource() returns an error,
mlxbf_i2c_init_resource() frees tmp_res before reading tmp_res->io to
get the error code. This results in a use-after-free.
Save the error code before freeing tmp_res. |
| In the Linux kernel, the following vulnerability has been resolved:
locking/rt: Fix the incorrect RCU protection in rt_spin_unlock()
rt_spin_unlock() releases the RCU protection before unlocking the
lock. That opens the door for the following UAF scenario:
T1 T2
spin_lock(&p->lock); rcu_read_lock();
invalidate(p); p = rcu_dereference(ptr);
rcu_assign_pointer(ptr, NULL); if (!p) return;
spin_unlock(&p->lock); spin_lock(&p->lock)
lock(&lock->lock);
rcu_read_lock();
kfree_rcu(p); rcu_read_unlock();
....
spin_unlock(&p->lock)
rcu_read_unlock(); // Ends grace period
rcu_do_batch()
kfree(p);
UAF -> rt_mutex_cmpxchg_release(&lock->lock...)
Regular spinlocks keep preemption disabled accross the unlock operation,
which provides full RCU protection, but the RT substitution fails to
resemble that. Same applies for the rwlock substitution.
Move the rcu_read_unlock() invocation past the unlock operations to match
the non-RT semantics. This makes it asymmetric vs. rt_xxx_lock(), but
that's harmless as the caller needs to hold RCU read lock across the lock
operation. The migrate_enable() call stays before the unlock operation
because there is no per CPU operation in the unlock path which would
require migration to be kept disabled. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: libertas_tf: fix use-after-free in lbtf_free_adapter()
lbtf_free_adapter() calls timer_delete(&priv->command_timer), which does
not wait for a running command_timer_fn() callback. lbtf_free_adapter()
runs on the teardown path right before ieee80211_free_hw() frees priv,
both in lbtf_remove_card() and in the probe error path. command_timer is
armed by mod_timer() in lbtf_cmd() whenever a firmware command is sent.
command_timer_fn() dereferences priv. If a command times out as the
device is removed, command_timer_fn() runs concurrently with teardown and
dereferences priv after it has been freed.
This is the same use-after-free that commit 03cc8f90d053 ("wifi: libertas:
fix use-after-free in lbs_free_adapter()") fixed in the sibling libertas
driver. The libertas_tf variant has the identical pattern and was left
unchanged. Use timer_delete_sync() so any in-flight callback completes
before priv is freed. |
| In the Linux kernel, the following vulnerability has been resolved:
tracing/user_events: Fix use-after-free in user_event_mm_dup()
user_event_mm_dup() walks the parent mm's enabler list locklessly under
rcu_read_lock() during fork() (from copy_process()); it does not take
event_mutex:
rcu_read_lock();
list_for_each_entry_rcu(enabler, &old_mm->enablers, mm_enablers_link)
enabler->event = user_event_get(orig->event);
user_event_enabler_destroy() removes an enabler from that list with
list_del_rcu() and then, without waiting for a grace period, drops the
enabler's user_event reference with user_event_put() and frees the enabler
with kfree(). A reader that loaded the enabler before the list_del_rcu()
can still be walking it, which leads to two use-after-frees:
- kfree(enabler) frees the enabler while that reader dereferences
enabler->event.
- user_event_put() may drop the last reference to the user_event, which
is then freed (via delayed_destroy_user_event() on a work queue), while
the same reader does user_event_get(orig->event) on it.
Both are reachable by an unprivileged task that can open user_events_data:
one multithreaded process that registers an enabler and then concurrently
unregisters it and calls fork() triggers the race. KASAN reports a
slab-use-after-free in user_event_mm_dup() during clone(), with a
"refcount_t: addition on 0" warning when the user_event is freed.
The enabler use-after-free was found first; the user_event one was reported
by XIAO WU, and the earlier enabler-only fix did not address it.
Defer both the user_event_put() and the kfree(enabler) to a work item
queued with queue_rcu_work(), so they run only after an RCU grace period,
once all readers walking the enabler list have finished. The put must run
in process context because user_event_put() takes event_mutex on the last
reference, so a work queue is used rather than call_rcu(). The now-unlocked
put lets the locked argument of user_event_enabler_destroy() be removed;
all callers are updated. |
| In the Linux kernel, the following vulnerability has been resolved:
fs/resctrl: Fix use-after-free during unmount
During unmount or failure teardown all mon_data structures that contain
monitoring event file private data are freed after which kernfs nodes are
removed. However, the RDT_DELETED flag is never set for the statically
allocated default resource group.
A concurrent reader of an event file associated with the default resource
group may, after dropping kernfs active protection, block on rdtgroup_mutex
while unmount proceeds to free the file private data and destroy the kernfs
node without waiting for the reader.
When the mutex is released, the reader wakes up, observes that RDT_DELETED
is not set for the default group, and dereferences the already-freed
file private data.
The scenario can be depicted as follows:
CPU0 CPU1
/*
* Default resource group's
* monitoring data accessible via
* kernfs file with kernfs_node::priv
* pointing to a struct mon_data.
* User opens the file for reading.
*/
rdtgroup_mondata_show() /* arch encounters fatal error */
rdtgroup_kn_lock_live() resctrl_exit()
atomic_inc(&rdtgroup_default.waitcount) cpus_read_lock()
kernfs_break_active_protection(kn) mutex_lock(&rdtgroup_mutex)
cpus_read_lock() resctrl_fs_teardown()
mutex_lock(&rdtgroup_mutex) rmdir_all_sub()
mon_put_kn_priv()
/* Delete all mon_data structures */
rdtgroup_destroy_root()
kernfs_destroy_root()
rdtgroup_default.kn = NULL
mutex_unlock(&rdtgroup_mutex)
/*
* rdtgroup_default.flags is empty so
* rdtgroup_kn_lock_live() returns
* &rdtgroup_default
*/
md = of->kn->priv;
/* md points to freed mon_data */
Set RDT_DELETED for the default group unconditionally since the flag does
not lead to the freeing of this statically allocated group.
Do not allow a new resctrl mount if there are any waiters on default group
of previous mount. A new mount will re-initialize the default group that
would appear to waiters from previous mount as though the default group is
accessible causing them to access the mon_data structures from the previous
mount that have been removed. |
| In the Linux kernel, the following vulnerability has been resolved:
scsi: xen: scsiback: Free the command tag on the TMR submit-failure path
scsiback_device_action() obtains a command tag in
scsiback_get_pend_req() and submits a task-management request with
target_submit_tmr(). When target_submit_tmr() fails it returns < 0 and
scsiback jumps to the err: label, which sends a response but frees
nothing, leaking the tag.
Impact: a pvSCSI guest can leak the command tags of a LUN's session,
stopping the LUN, by issuing VSCSIIF_ACT_SCSI_ABORT or RESET requests
whenever target_submit_tmr() fails.
transport_generic_free_cmd() cannot be used here. By the time
target_submit_tmr() returns an error it has already run
__target_init_cmd() (so se_cmd->cmd_kref is one, not zero), and on its
target_get_sess_cmd() error path it has freed se_cmd->se_tmr_req via
core_tmr_release_req() while leaving SCF_SCSI_TMR_CDB set and the
pointer dangling. Letting the command release run target_free_cmd_mem()
would then double-free se_tmr_req.
Use the same helper, which returns just the tag, on this path too. |
| In the Linux kernel, the following vulnerability has been resolved:
mac802154: remove interfaces with RCU list deletion
Queue wake, stop, and disable paths walk local->interfaces under RCU.
The bulk hardware teardown path removes entries with list_del(), so an
asynchronous transmit completion can follow a poisoned list node in
ieee802154_wake_queue().
Use list_del_rcu() as in the single-interface removal path. The following
unregister_netdevice() waits for in-flight RCU readers before freeing the
netdevice, so no separate grace-period wait is needed. |
| In the Linux kernel, the following vulnerability has been resolved:
fs/resctrl: Fix double-add of pseudo-locked region's RMID to free list
A pseudo-locked group's RMID is freed when it is created. On unmount
rmdir_all_sub() unconditionally frees all RMID of all groups, resulting
in a double-free of the pseudo-locked group's RMID. The consequence of this
is that the original free results in the pseudo-locked group's RMID being
added to the rmid_free_lru linked list and the second free then attempts
to add the same RMID entry to the rmid_free_lru again.
Do not double-free a pseudo-locked group's RMID. |
| JupyterLab (pip package 'jupyterlab') versions >=4.1.0,<=4.5.9 and >=4.6.0,<=4.6.1 contain a plugin manager lock-rule enforcement bypass. Two server-side enforcement gaps allow an authenticated user to circumvent administrator lock rules by making direct requests to the /lab/api/plugins endpoint, enabling or disabling plugins that were locked — including child plugins of multi-plugin extensions and plugins locked via the 'lock all' mechanism. This can impact data integrity and bypass hardening or restrictions (e.g., download/upload limits) implemented through locked plugins. Fixed in versions 4.6.2 and 4.5.10. |
| Zephyr's dynamic kernel-object disposal path unref_check() in kernel/userspace/userspace.c frees an object's storage (k_free(dyn->data)) once its reference count reaches zero, after running a per-object-type cleanup. The cleanup switch handled only K_OBJ_MSGQ and K_OBJ_STACK; there was no K_OBJ_TIMER case. A dynamically-allocated, initialized, and armed k_timer keeps its embedded struct _timeout dnode linked in the global timeout queue (_timeout_q), so freeing the timer storage without cancelling the timeout leaves a dangling node in that queue.
When the timer next expires, the timeout machinery walks _timeout_q and invokes z_timer_expiration_handler() on the freed node, dereferencing and writing freed (and reusable) kernel heap in kernel/ISR context. This is a deterministic use-after-free that does not depend on SMP: the queued node is simply never unlinked at free time.
The disposal is reachable from an unprivileged user thread under CONFIG_USERSPACE + CONFIG_DYNAMIC_OBJECTS: a thread that holds the last permission on such a timer drops it via the k_object_release() syscall (or by exiting, through k_thread_perms_all_clear()), and can arm the timer itself via the k_timer_start() syscall. The free and the expiration handler run at kernel privilege while the actor is a user thread, so the bug is a sandbox-escape memory-corruption primitive usable for privilege escalation. The fix adds k_timer_cleanup() (cancel the timeout and wait for any in-flight handler) and calls it for K_OBJ_TIMER before freeing. |
| A use-after-free exists in the Zephyr second-generation work queue (kernel/work.c) in the handling of delayable work timeouts. When a delayable work item's timeout has been dequeued and its handler work_timeout() is in flight (blocked acquiring the work-queue spinlock), a concurrent cancellation does not wait for that handler to finish. In unschedule_locked() the pre-fix code called z_abort_timeout(), which for an already-announcing record returns -EINVAL without removing it; cancel_async_locked() then observes the work as idle, so even k_work_cancel_delayable_sync() and k_work_flush_delayable() return without blocking on the in-flight handler.
Because those are the APIs the kernel header documents as the safe way to cancel before freeing a k_work_delayable, a caller that frees the object immediately after a successful sync cancel can race the still-pending handler. work_timeout() subsequently dereferences the freed record: it reads to->dticks via z_is_timeout_handler_canceled() and, if the freed slot has been reused so the bail check fails, performs a read-modify-write of wp->flags (K_WORK_DELAYED_BIT) and submits work against a stale dw->queue pointer — a use-after-free read and write.
The k_work API is kernel-mode only (no __syscall entry point), so this is a kernel-internal concurrency defect rather than a userspace privilege escalation. Triggering it requires an SMP build and a subsystem that schedules and then frees (or reschedules) a delayable work item in the narrow window while its timeout is announcing; an attacker able to influence the timing of such teardown (for example via connection churn driving subsystem timers) has a plausible but probabilistic path. The impact is kernel memory corruption or crash (denial of service).
The fix makes unschedule_locked() wait, by spinning on z_try_abort_timeout() returning -EAGAIN while releasing and re-acquiring the work spinlock, until any in-flight handler completes before returning, and switches work_timeout() to atomic K_WORK_DELAYED_BIT ownership. This closes both the free-then-handler use-after-free and the related reschedule early-fire race. |
| Use after free in Active Directory Certificate Services (AD CS) allows an authorized attacker to execute code over a network. |
