Security Vulnerabilities - CVEs Published In May 2026
In the Linux kernel, the following vulnerability has been resolved:
ibmasm: fix heap over-read in ibmasm_send_i2o_message()
The ibmasm_send_i2o_message() function uses get_dot_command_size() to
compute the byte count for memcpy_toio(), but this value is derived from
user-controlled fields in the dot_command_header (command_size: u8,
data_size: u16) and is never validated against the actual allocation size.
A root user can write a small buffer with inflated header fields, causing
memcpy_toio() to read up to ~65 KB past the end of the allocation into
adjacent kernel heap, which is then forwarded to the service processor
over MMIO.
Silently clamping the copy size is not sufficient: if the header fields
claim a larger size than the buffer, the SP receives a dot command whose
own header is inconsistent with the I2O message length, which can cause
the SP to desynchronize. Reject such commands outright by returning
failure.
Validate command_size before calling get_mfa_inbound() to avoid leaking
an I2O message frame: reading INBOUND_QUEUE_PORT dequeues a hardware
frame from the controller's free pool, and returning without a
corresponding set_mfa_inbound() call would permanently exhaust it.
Additionally, clamp command_size to I2O_COMMAND_SIZE before the
memcpy_toio() so the MMIO write stays within the I2O message frame,
consistent with the clamping already performed by outgoing_message_size()
for the header field.
CVSS Score
7.1
EPSS Score
0.001
Published
2026-05-27
In the Linux kernel, the following vulnerability has been resolved:
selinux: fix overlayfs mmap() and mprotect() access checks
The existing SELinux security model for overlayfs is to allow access if
the current task is able to access the top level file (the "user" file)
and the mounter's credentials are sufficient to access the lower
level file (the "backing" file). Unfortunately, the current code does
not properly enforce these access controls for both mmap() and mprotect()
operations on overlayfs filesystems.
This patch makes use of the newly created security_mmap_backing_file()
LSM hook to provide the missing backing file enforcement for mmap()
operations, and leverages the backing file API and new LSM blob to
provide the necessary information to properly enforce the mprotect()
access controls.
CVSS Score
7.1
EPSS Score
0.001
Published
2026-05-27
In the Linux kernel, the following vulnerability has been resolved:
apparmor: Fix string overrun due to missing termination
When booting Ubuntu 26.04 with Linux 7.0-rc4 on an ARM64 Qualcomm
Snapdragon X1 we see a string buffer overrun:
BUG: KASAN: slab-out-of-bounds in aa_dfa_match (security/apparmor/match.c:535)
Read of size 1 at addr ffff0008901cc000 by task snap-update-ns/2120
CPU: 5 UID: 60578 PID: 2120 Comm: snap-update-ns Not tainted 7.0.0-rc4+ #22 PREEMPTLAZY
Hardware name: LENOVO 83ED/LNVNB161216, BIOS NHCN60WW 09/11/2025
Call trace:
show_stack (arch/arm64/kernel/stacktrace.c:501) (C)
dump_stack_lvl (lib/dump_stack.c:122)
print_report (mm/kasan/report.c:379 mm/kasan/report.c:482)
kasan_report (mm/kasan/report.c:597)
__asan_report_load1_noabort (mm/kasan/report_generic.c:378)
aa_dfa_match (security/apparmor/match.c:535)
match_mnt_path_str (security/apparmor/mount.c:244 security/apparmor/mount.c:336)
match_mnt (security/apparmor/mount.c:371)
aa_bind_mount (security/apparmor/mount.c:447 (discriminator 4))
apparmor_sb_mount (security/apparmor/lsm.c:719 (discriminator 1))
security_sb_mount (security/security.c:1062 (discriminator 31))
path_mount (fs/namespace.c:4101)
__arm64_sys_mount (fs/namespace.c:4172 fs/namespace.c:4361 fs/namespace.c:4338 fs/namespace.c:4338)
invoke_syscall.constprop.0 (arch/arm64/kernel/syscall.c:35 arch/arm64/kernel/syscall.c:49)
el0_svc_common.constprop.0 (./include/linux/thread_info.h:142 (discriminator 2) arch/arm64/kernel/syscall.c:140 (discriminator 2))
do_el0_svc (arch/arm64/kernel/syscall.c:152)
el0_svc (arch/arm64/kernel/entry-common.c:80 arch/arm64/kernel/entry-common.c:725)
el0t_64_sync_handler (arch/arm64/kernel/entry-common.c:744)
el0t_64_sync (arch/arm64/kernel/entry.S:596)
Allocated by task 2120:
kasan_save_stack (mm/kasan/common.c:58)
kasan_save_track (./arch/arm64/include/asm/current.h:19 mm/kasan/common.c:70 mm/kasan/common.c:79)
kasan_save_alloc_info (mm/kasan/generic.c:571)
__kasan_kmalloc (mm/kasan/common.c:419)
__kmalloc_noprof (./include/linux/kasan.h:263 mm/slub.c:5260 mm/slub.c:5272)
aa_get_buffer (security/apparmor/lsm.c:2201)
aa_bind_mount (security/apparmor/mount.c:442)
apparmor_sb_mount (security/apparmor/lsm.c:719 (discriminator 1))
security_sb_mount (security/security.c:1062 (discriminator 31))
path_mount (fs/namespace.c:4101)
__arm64_sys_mount (fs/namespace.c:4172 fs/namespace.c:4361 fs/namespace.c:4338 fs/namespace.c:4338)
invoke_syscall.constprop.0 (arch/arm64/kernel/syscall.c:35 arch/arm64/kernel/syscall.c:49)
el0_svc_common.constprop.0 (./include/linux/thread_info.h:142 (discriminator 2) arch/arm64/kernel/syscall.c:140 (discriminator 2))
do_el0_svc (arch/arm64/kernel/syscall.c:152)
el0_svc (arch/arm64/kernel/entry-common.c:80 arch/arm64/kernel/entry-common.c:725)
el0t_64_sync_handler (arch/arm64/kernel/entry-common.c:744)
el0t_64_sync (arch/arm64/kernel/entry.S:596)
The buggy address belongs to the object at ffff0008901ca000
which belongs to the cache kmalloc-rnd-06-8k of size 8192
The buggy address is located 0 bytes to the right of
allocated 8192-byte region [ffff0008901ca000, ffff0008901cc000)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x9101c8
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:-1 pincount:0
flags: 0x8000000000000040(head|zone=2)
page_type: f5(slab)
raw: 8000000000000040 ffff000800016c40 fffffdffe2d14e10 ffff000800015c70
raw: 0000000000000000 0000000800010001 00000000f5000000 0000000000000000
head: 8000000000000040 ffff000800016c40 fffffdffe2d14e10 ffff000800015c70
head: 0000000000000000 0000000800010001 00000000f5000000 0000000000000000
head: 8000000000000003 fffffdffe2407201 fffffdffffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff0008901cbf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff0008
---truncated---
CVSS Score
7.1
EPSS Score
0.002
Published
2026-05-27
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: hci_event: fix potential UAF in SSP passkey handlers
hci_conn lookup and field access must be covered by hdev lock in
hci_user_passkey_notify_evt() and hci_keypress_notify_evt(), otherwise
the connection can be freed concurrently.
Extend the hci_dev_lock critical section to cover all conn usage in both
handlers.
Keep the existing keypress notification behavior unchanged by routing
the early exits through a common unlock path.
CVSS Score
8.8
EPSS Score
0.003
Published
2026-05-27
In the Linux kernel, the following vulnerability has been resolved:
landlock: Fix LOG_SUBDOMAINS_OFF inheritance across fork()
hook_cred_transfer() only copies the Landlock security blob when the
source credential has a domain. This is inconsistent with
landlock_restrict_self() which can set LOG_SUBDOMAINS_OFF on a
credential without creating a domain (via the ruleset_fd=-1 path): the
field is committed but not preserved across fork() because the child's
prepare_creds() calls hook_cred_transfer() which skips the copy when
domain is NULL.
This breaks the documented use case where a process mutes subdomain logs
before forking sandboxed children: the children lose the muting and
their domains produce unexpected audit records.
Fix this by unconditionally copying the Landlock credential blob.
CVSS Score
3.3
EPSS Score
0.001
Published
2026-05-27
In the Linux kernel, the following vulnerability has been resolved:
media: amphion: Fix race between m2m job_abort and device_run
Fix kernel panic caused by race condition where v4l2_m2m_ctx_release()
frees m2m_ctx while v4l2_m2m_try_run() is about to call device_run
with the same context.
Race sequence:
v4l2_m2m_try_run(): v4l2_m2m_ctx_release():
lock/unlock v4l2_m2m_cancel_job()
job_abort()
v4l2_m2m_job_finish()
kfree(m2m_ctx) <- frees ctx
device_run() <- use-after-free crash at 0x538
Crash trace:
Unable to handle kernel read from unreadable memory at virtual address
0000000000000538
v4l2_m2m_try_run+0x78/0x138
v4l2_m2m_device_run_work+0x14/0x20
The amphion vpu driver does not rely on the m2m framework's device_run
callback to perform encode/decode operations.
Fix the race by preventing m2m framework job scheduling entirely:
- Add job_ready callback returning 0 (no jobs ready for m2m framework)
- Remove job_abort callback to avoid the race condition
CVSS Score
7.8
EPSS Score
0.001
Published
2026-05-27
In the Linux kernel, the following vulnerability has been resolved:
KVM: nSVM: Always use NextRIP as vmcb02's NextRIP after first L2 VMRUN
For guests with NRIPS disabled, L1 does not provide NextRIP when running
an L2 with an injected soft interrupt, instead it advances the current RIP
before running it. KVM uses the current RIP as the NextRIP in vmcb02 to
emulate a CPU without NRIPS.
However, after L2 runs the first time, NextRIP will be updated by the CPU
and/or KVM, and the current RIP is no longer the correct value to use in
vmcb02. Hence, after save/restore, use the current RIP if and only if a
nested run is pending, otherwise use NextRIP. Give soft_int_next_rip the
same treatment, as it's the same logic, just for a narrower use case.
[sean: give soft_int_next_rip the same treatment]
CVSS Score
5.5
EPSS Score
0.001
Published
2026-05-27
In the Linux kernel, the following vulnerability has been resolved:
crypto: qat - fix IRQ cleanup on 6xxx probe failure
When adf_dev_up() partially completes and then fails, the IRQ
handlers registered during adf_isr_resource_alloc() are not detached
before the MSI-X vectors are released.
Since the device is enabled with pcim_enable_device(), calling
pci_alloc_irq_vectors() internally registers pcim_msi_release() as a
devres action. On probe failure, devres runs pcim_msi_release() which
calls pci_free_irq_vectors(), tearing down the MSI-X vectors while IRQ
handlers (for example 'qat0-bundle0') are still attached. This causes
remove_proc_entry() warnings:
[ 22.163964] remove_proc_entry: removing non-empty directory 'irq/143', leaking at least 'qat0-bundle0'
Moving the devm_add_action_or_reset() before adf_dev_up() does not solve
the problem since devres runs in LIFO order and pcim_msi_release(),
registered later inside adf_dev_up(), would still fire before
adf_device_down().
Fix by calling adf_dev_down() explicitly when adf_dev_up() fails, to
properly free IRQ handlers before devres releases the MSI-X vectors.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-05-27
In the Linux kernel, the following vulnerability has been resolved:
jbd2: fix deadlock in jbd2_journal_cancel_revoke()
Commit f76d4c28a46a ("fs/jbd2: use sleeping version of
__find_get_block()") changed jbd2_journal_cancel_revoke() to use
__find_get_block_nonatomic() which holds the folio lock instead of
i_private_lock. This breaks the lock ordering (folio -> buffer) and
causes an ABBA deadlock when the filesystem blocksize < pagesize:
T1 T2
ext4_mkdir()
ext4_init_new_dir()
ext4_append()
ext4_getblk()
lock_buffer() <- A
sync_blockdev()
blkdev_writepages()
writeback_iter()
writeback_get_folio()
folio_lock() <- B
ext4_journal_get_create_access()
jbd2_journal_cancel_revoke()
__find_get_block_nonatomic()
folio_lock() <- B
block_write_full_folio()
lock_buffer() <- A
This can occasionally cause generic/013 to hang.
Fix by only calling __find_get_block_nonatomic() when the passed
buffer_head doesn't belong to the bdev, which is the only case that we
need to look up its bdev alias. Otherwise, the lookup is redundant since
the found buffer_head is equal to the one we passed in.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-05-27
In the Linux kernel, the following vulnerability has been resolved:
ext4: fix missing brelse() in ext4_xattr_inode_dec_ref_all()
The commit c8e008b60492 ("ext4: ignore xattrs past end")
introduced a refcount leak in when block_csum is false.
ext4_xattr_inode_dec_ref_all() calls ext4_get_inode_loc() to
get iloc.bh, but never releases it with brelse().
CVSS Score
5.5
EPSS Score
0.001
Published
2026-05-27