Security Vulnerabilities - CVEs Published In April 2026
In the Linux kernel, the following vulnerability has been resolved:
futex: Require sys_futex_requeue() to have identical flags
Nicholas reported that his LLM found it was possible to create a UaF
when sys_futex_requeue() is used with different flags. The initial
motivation for allowing different flags was the variable sized futex,
but since that hasn't been merged (yet), simply mandate the flags are
identical, as is the case for the old style sys_futex() requeue
operations.
CVSS Score
7.8
EPSS Score
0.002
Published
2026-04-24
In the Linux kernel, the following vulnerability has been resolved:
futex: Clear stale exiting pointer in futex_lock_pi() retry path
Fuzzying/stressing futexes triggered:
WARNING: kernel/futex/core.c:825 at wait_for_owner_exiting+0x7a/0x80, CPU#11: futex_lock_pi_s/524
When futex_lock_pi_atomic() sees the owner is exiting, it returns -EBUSY
and stores a refcounted task pointer in 'exiting'.
After wait_for_owner_exiting() consumes that reference, the local pointer
is never reset to nil. Upon a retry, if futex_lock_pi_atomic() returns a
different error, the bogus pointer is passed to wait_for_owner_exiting().
CPU0 CPU1 CPU2
futex_lock_pi(uaddr)
// acquires the PI futex
exit()
futex_cleanup_begin()
futex_state = EXITING;
futex_lock_pi(uaddr)
futex_lock_pi_atomic()
attach_to_pi_owner()
// observes EXITING
*exiting = owner; // takes ref
return -EBUSY
wait_for_owner_exiting(-EBUSY, owner)
put_task_struct(); // drops ref
// exiting still points to owner
goto retry;
futex_lock_pi_atomic()
lock_pi_update_atomic()
cmpxchg(uaddr)
*uaddr ^= WAITERS // whatever
// value changed
return -EAGAIN;
wait_for_owner_exiting(-EAGAIN, exiting) // stale
WARN_ON_ONCE(exiting)
Fix this by resetting upon retry, essentially aligning it with requeue_pi.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-04-24
In the Linux kernel, the following vulnerability has been resolved:
xfs: scrub: unlock dquot before early return in quota scrub
xchk_quota_item can return early after calling xchk_fblock_process_error.
When that helper returns false, the function returned immediately without
dropping dq->q_qlock, which can leave the dquot lock held and risk lock
leaks or deadlocks in later quota operations.
Fix this by unlocking dq->q_qlock before the early return.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-04-24
In the Linux kernel, the following vulnerability has been resolved:
tracing: Fix trace_marker copy link list updates
When the "copy_trace_marker" option is enabled for an instance, anything
written into /sys/kernel/tracing/trace_marker is also copied into that
instances buffer. When the option is set, that instance's trace_array
descriptor is added to the marker_copies link list. This list is protected
by RCU, as all iterations uses an RCU protected list traversal.
When the instance is deleted, all the flags that were enabled are cleared.
This also clears the copy_trace_marker flag and removes the trace_array
descriptor from the list.
The issue is after the flags are called, a direct call to
update_marker_trace() is performed to clear the flag. This function
returns true if the state of the flag changed and false otherwise. If it
returns true here, synchronize_rcu() is called to make sure all readers
see that its removed from the list.
But since the flag was already cleared, the state does not change and the
synchronization is never called, leaving a possible UAF bug.
Move the clearing of all flags below the updating of the copy_trace_marker
option which then makes sure the synchronization is performed.
Also use the flag for checking the state in update_marker_trace() instead
of looking at if the list is empty.
CVSS Score
7.8
EPSS Score
0.001
Published
2026-04-24
In the Linux kernel, the following vulnerability has been resolved:
x86/platform/uv: Handle deconfigured sockets
When a socket is deconfigured, it's mapped to SOCK_EMPTY (0xffff). This causes
a panic while allocating UV hub info structures.
Fix this by using NUMA_NO_NODE, allowing UV hub info structures to be
allocated on valid nodes.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-04-24
In the Linux kernel, the following vulnerability has been resolved:
crash_dump: don't log dm-crypt key bytes in read_key_from_user_keying
When debug logging is enabled, read_key_from_user_keying() logs the first
8 bytes of the key payload and partially exposes the dm-crypt key. Stop
logging any key bytes.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-04-24
In the Linux kernel, the following vulnerability has been resolved:
firmware: arm_scmi: Fix NULL dereference on notify error path
Since commit b5daf93b809d1 ("firmware: arm_scmi: Avoid notifier
registration for unsupported events") the call chains leading to the helper
__scmi_event_handler_get_ops expect an ERR_PTR to be returned on failure to
get an handler for the requested event key, while the current helper can
still return a NULL when no handler could be found or created.
Fix by forcing an ERR_PTR return value when the handler reference is NULL.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-04-24
In the Linux kernel, the following vulnerability has been resolved:
NFC: nxp-nci: allow GPIOs to sleep
Allow the firmware and enable GPIOs to sleep.
This fixes a `WARN_ON' and allows the driver to operate GPIOs which are
connected to I2C GPIO expanders.
-- >8 --
kernel: WARNING: CPU: 3 PID: 2636 at drivers/gpio/gpiolib.c:3880 gpiod_set_value+0x88/0x98
-- >8 --
CVSS Score
5.5
EPSS Score
0.001
Published
2026-04-24
In the Linux kernel, the following vulnerability has been resolved:
net: bonding: fix NULL deref in bond_debug_rlb_hash_show
rlb_clear_slave intentionally keeps RLB hash-table entries on
the rx_hashtbl_used_head list with slave set to NULL when no
replacement slave is available. However, bond_debug_rlb_hash_show
visites client_info->slave without checking if it's NULL.
Other used-list iterators in bond_alb.c already handle this NULL-slave
state safely:
- rlb_update_client returns early on !client_info->slave
- rlb_req_update_slave_clients, rlb_clear_slave, and rlb_rebalance
compare slave values before visiting
- lb_req_update_subnet_clients continues if slave is NULL
The following NULL deref crash can be trigger in
bond_debug_rlb_hash_show:
[ 1.289791] BUG: kernel NULL pointer dereference, address: 0000000000000000
[ 1.292058] RIP: 0010:bond_debug_rlb_hash_show (drivers/net/bonding/bond_debugfs.c:41)
[ 1.293101] RSP: 0018:ffffc900004a7d00 EFLAGS: 00010286
[ 1.293333] RAX: 0000000000000000 RBX: ffff888102b48200 RCX: ffff888102b48204
[ 1.293631] RDX: ffff888102b48200 RSI: ffffffff839daad5 RDI: ffff888102815078
[ 1.293924] RBP: ffff888102815078 R08: ffff888102b4820e R09: 0000000000000000
[ 1.294267] R10: 0000000000000000 R11: 0000000000000000 R12: ffff888100f929c0
[ 1.294564] R13: ffff888100f92a00 R14: 0000000000000001 R15: ffffc900004a7ed8
[ 1.294864] FS: 0000000001395380(0000) GS:ffff888196e75000(0000) knlGS:0000000000000000
[ 1.295239] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1.295480] CR2: 0000000000000000 CR3: 0000000102adc004 CR4: 0000000000772ef0
[ 1.295897] Call Trace:
[ 1.296134] seq_read_iter (fs/seq_file.c:231)
[ 1.296341] seq_read (fs/seq_file.c:164)
[ 1.296493] full_proxy_read (fs/debugfs/file.c:378 (discriminator 1))
[ 1.296658] vfs_read (fs/read_write.c:572)
[ 1.296981] ksys_read (fs/read_write.c:717)
[ 1.297132] do_syscall_64 (arch/x86/entry/syscall_64.c:63 (discriminator 1) arch/x86/entry/syscall_64.c:94 (discriminator 1))
[ 1.297325] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
Add a NULL check and print "(none)" for entries with no assigned slave.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-04-24
In the Linux kernel, the following vulnerability has been resolved:
drm/xe: Fix missing runtime PM reference in ccs_mode_store
ccs_mode_store() calls xe_gt_reset() which internally invokes
xe_pm_runtime_get_noresume(). That function requires the caller
to already hold an outer runtime PM reference and warns if none
is held:
[46.891177] xe 0000:03:00.0: [drm] Missing outer runtime PM protection
[46.891178] WARNING: drivers/gpu/drm/xe/xe_pm.c:885 at
xe_pm_runtime_get_noresume+0x8b/0xc0
Fix this by protecting xe_gt_reset() with the scope-based
guard(xe_pm_runtime)(xe), which is the preferred form when
the reference lifetime matches a single scope.
v2:
- Use scope-based guard(xe_pm_runtime)(xe) (Shuicheng)
- Update commit message accordingly
(cherry picked from commit 7937ea733f79b3f25e802a0c8360bf7423856f36)
CVSS Score
5.5
EPSS Score
0.001
Published
2026-04-24