Linux: >> Linux Kernel >> 6.18.17 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
fuse-uring: remove request-less entries from ent_w_req_queue to fix NULL deref
If a copy into the userspace ring buffer fails, a request will be
terminated and fuse_uring_req_end() will set ent->fuse_req to NULL but
it will leave the entry on ent_w_req_queue in FRRS_FUSE_REQ state. This
can lead to a NULL deref if the request expiration logic scans
ent_w_req_queue in the window before the entry is moved off it.
Fix this by taking the entry off ent_w_req_queue and changing its state
from FRRS_FUSE_REQ to FRRS_INVALID before terminating the request.
CVSS Score
5.5
EPSS Score
0.002
Published
2026-07-25
In the Linux kernel, the following vulnerability has been resolved:
xfs: don't wrap around quota ids in dqiterate
LOLLM noticed that q_id is an unsigned 32-bit variable. If it happens
to be set to XFS_DQ_ID_MAX due to a filesystem that actually has a dquot
for ID_MAX, then this addition will truncate to zero and the iteration
starts over. Fix this by casting to u64.
CVSS Score
5.5
EPSS Score
0.002
Published
2026-07-25
In the Linux kernel, the following vulnerability has been resolved:
kernel/fork: clear PF_BLOCK_TS in copy_process()
PF_BLOCK_TS is only set in blk_time_get_ns() when current->plug is
non-NULL, and blk_finish_plug() clears it via __blk_flush_plug()
before NULLing the plug pointer. copy_process() breaks the
invariant by inheriting PF_BLOCK_TS from the parent while resetting
the child's plug to NULL.
Clear PF_BLOCK_TS alongside that assignment so callers can rely on
"PF_BLOCK_TS set implies current->plug != NULL" and dereference
current->plug unguarded.
CVSS Score
5.5
EPSS Score
0.002
Published
2026-07-24
In the Linux kernel, the following vulnerability has been resolved:
NTB: epf: Avoid pci_iounmap() with offset when PEER_SPAD and CONFIG share BAR
When BAR_PEER_SPAD and BAR_CONFIG share one PCI BAR, the module teardown
path ends up calling pci_iounmap() on the same iomem with some offset,
which is unnecessary and triggers a kernel warning like the following:
Trying to vunmap() nonexistent vm area (0000000069a5ffe8)
WARNING: mm/vmalloc.c:3470 at vunmap+0x58/0x68, CPU#5: modprobe/2937
[...]
Call trace:
vunmap+0x58/0x68 (P)
iounmap+0x34/0x48
pci_iounmap+0x2c/0x40
ntb_epf_pci_remove+0x44/0x80 [ntb_hw_epf]
pci_device_remove+0x48/0xf8
device_remove+0x50/0x88
device_release_driver_internal+0x1c8/0x228
driver_detach+0x50/0xb0
bus_remove_driver+0x74/0x100
driver_unregister+0x34/0x68
pci_unregister_driver+0x34/0xa0
ntb_epf_pci_driver_exit+0x14/0xfe0 [ntb_hw_epf]
[...]
Fix it by unmapping only when PEER_SPAD and CONFIG use difference bars.
CVSS Score
5.5
EPSS Score
0.002
Published
2026-07-24
In the Linux kernel, the following vulnerability has been resolved:
wifi: iwlwifi: mld: validate sta_mask before ffs() in BA session handlers
Three BA session handlers use ffs(ba_data->sta_mask) - 1 to derive a
station ID without checking that sta_mask is non-zero. When sta_mask is
zero, ffs() returns 0 and the subtraction wraps to 0xFFFFFFFF, causing
an out-of-bounds access on fw_id_to_link_sta[].
Add WARN_ON_ONCE(!ba_data->sta_mask) guards before each ffs() call,
consistent with the existing check in iwl_mld_ampdu_rx_start().
CVSS Score
8.8
EPSS Score
0.002
Published
2026-07-24
In the Linux kernel, the following vulnerability has been resolved:
pwrseq: core: fix use-after-free in pwrseq_debugfs_seq_next()
pwrseq_debugfs_seq_next() declares 'next' with __free(put_device),
which causes put_device() to be called on the returned pointer when
the variable goes out of scope. This results in a use-after-free
since the seq_file framework receives a pointer whose reference has
already been dropped.
Simply removing __free(put_device) would fix the UAF but would leak
the reference acquired by bus_find_next_device(), as stop() only
calls up_read(&pwrseq_sem) and never releases the device reference.
Fix this by making the reference counting consistent across all
seq_file callbacks, matching the standard pattern used by PCI and
SCSI:
- start(): use get_device() so it returns a referenced pointer.
- next(): explicitly put_device(curr) to release the previous
device's reference (no NULL check needed - the seq_file framework
only calls next() while the previous return was non-NULL).
- stop(): put_device(data) to release the last iterated device's
reference, with a NULL guard since stop() may be called with NULL
when start() returned NULL or next() reached end-of-sequence.
CVSS Score
7.8
EPSS Score
0.001
Published
2026-07-24
In the Linux kernel, the following vulnerability has been resolved:
MIPS: DEC: Prevent initial console buffer from landing in XKPHYS
In 64-bit configurations calling the initial console output handler from
a kernel thread other than the initial one will result in a situation
where the stack has been placed in the XKPHYS 64-bit memory segment and
consequently so has been the buffer allocated there that is used as the
argument corresponding to the `%s' output conversion specifier for the
firmware's printf() entry point.
This 64-bit address will then be truncated by 32-bit firmware, resulting
in an attempt to access the wrong memory location, which in turn will
cause all kinds of unpredictable behaviour, such as a kernel crash:
Console: colour dummy device 160x64
Calibrating delay loop... 49.36 BogoMIPS (lpj=192512)
pid_max: default: 32768 minimum: 301
CPU 0 Unable to handle kernel paging request at virtual address 000000000203bd00, epc == ffffffffbfc08364, ra == ffffffffbfc08800
Oops[#1]:
CPU: 0 PID: 0 Comm: swapper Not tainted 5.18.0-rc2-00254-gfb649bda6f56-dirty #121
$ 0 : 0000000000000000 0000000000000001 0000000000000023 ffffffff80684ba0
$ 4 : 000000000203bd00 ffffffffbfc0f3b4 ffffffffffffffff 0000000000000073
$ 8 : 0a303d7469000000 0000000000000000 0000000000000073 ffffffffbfc0f473
$12 : 0000000000000002 0000000000000000 ffffffff80684c1c 0000000000000000
$16 : 0000000000000000 ffffffff80596dc9 0000000000000000 ffffffffbfc09240
$20 : ffffffff80684c40 ffffffffbfc0f400 000000000000002d 000000000000002b
$24 : ffffffffffffffbf 000000000203bd00
$28 : ffffffff805f0000 ffffffff80684b58 0000000000000030 ffffffffbfc08800
Hi : 0000000000000000
Lo : 0000000000000aa8
epc : ffffffffbfc08364 0xffffffffbfc08364
ra : ffffffffbfc08800 0xffffffffbfc08800
Status: 140120e2 KX SX UX KERNEL EXL
Cause : 00000008 (ExcCode 02)
BadVA : 000000000203bd00
PrId : 00000430 (R4000SC)
Modules linked in:
Process swapper (pid: 0, threadinfo=(____ptrval____), task=(____ptrval____), tls=0000000000000000)
Stack : 0000000000000000 0000000000000000 0000000000000000 0000004d0000004d
80684cc0806a2a40 80596dc80000004d 8061000000000000 bfc0850c80684c38
0000000000000000 000000000203bd00 0000000000000000 0000000000000000
0000000000000000 00000000bfc0f3b4 0000000000000000 0000000000000000
0000000000000000 0000000000000000 0000000000000000 0000000000000000
0000000000000000 0000000000000000 0000000000000000 0000000000000000
0000002500000000 0000000000000000 0000000000000000 802c1a7400000000
0203bd0080596dc8 0203bd4d69000000 6c61632000000018 5f746567646e6172
6c616320625f6d6f 5f736e5f6d6f7266 206361323778302b 303d74696e726320
806a0a38806b0000 806a0a38806b0000 00000000806b0000 80683c58806b0000
...
Call Trace:
Code: a082ffff 03e00008 00601021 <80820000> 00001821 10400005 24840001 80820000 24630001
---[ end trace 0000000000000000 ]---
Kernel panic - not syncing: Fatal exception in interrupt
KN04 V2.1k (PC: 0xa0026768, SP: 0x806848e8)
>>
In this case the pointer in $4 was truncated from 0x980000000203bd00 to
0x000000000203bd00.
This may happen when no final console driver has been enabled in the
configuration and consequently the initial console continues being used
late into bootstrap or with an upcoming change that will switch the zs
driver to use a platform device, which in turn will make the console
handover happen only after other kernel threads have already been
started.
Fix the issue by making the buffer static and initdata, and therefore
placed in the CKSEG0 32-bit compatibility segment, observing that the
console output handler is called with the console lock held, implying
no need for this code to be reentrant. Add an assertion to verify the
buffer actually has been placed in a compatibility segment.
CVSS Score
5.5
EPSS Score
0.002
Published
2026-07-24
In the Linux kernel, the following vulnerability has been resolved:
power: reset: linkstation-poweroff: fix use-after-free in the linkstation_poweroff_init()
Move of_node_put(dn) after the of_match_node() call, which still needs
the node pointer. The node reference is correctly released after use.
CVSS Score
7.8
EPSS Score
0.002
Published
2026-07-24
In the Linux kernel, the following vulnerability has been resolved:
KVM: x86: hyper-v: Bound the bank index when querying sparse banks
When checking if a VP ID is included in a sparse bank set, explicitly check
that the ID can actually be contained in a sparse bank (the TLFS allows for
a maximum of 64 banks of 64 vCPUs each). When handling a paravirtual TLB
flush for L2, the VP ID is copied verbatim from the enlightened VMCS,
without any bounds check, i.e. isn't guaranteed to be under the limit of
4096.
Failure to check the bounds of the VP ID leads to an out-of-bounds read
when testing the sparse bank, and super strictly speaking could lead to KVM
performing an unnecessary TLB flush for an L2 vCPU.
==================================================================
BUG: KASAN: use-after-free in hv_is_vp_in_sparse_set+0x85/0x100 [kvm]
Read of size 8 at addr ffff88811ba5f598 by task hyperv_evmcs/2802
CPU: 12 UID: 1000 PID: 2802 Comm: hyperv_evmcs Not tainted 7.1.0-rc2 #7 PREEMPT
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
Call Trace:
<TASK>
dump_stack_lvl+0x51/0x60
print_report+0xcb/0x5d0
kasan_report+0xb4/0xe0
kasan_check_range+0x35/0x1b0
hv_is_vp_in_sparse_set+0x85/0x100 [kvm]
kvm_hv_flush_tlb+0xe9e/0x16c0 [kvm]
kvm_hv_hypercall+0xe6b/0x1e60 [kvm]
vmx_handle_exit+0x485/0x1b60 [kvm_intel]
kvm_arch_vcpu_ioctl_run+0x22e3/0x5070 [kvm]
kvm_vcpu_ioctl+0x5d0/0x10c0 [kvm]
__x64_sys_ioctl+0x129/0x1a0
do_syscall_64+0xb9/0xcf0
entry_SYSCALL_64_after_hwframe+0x4b/0x53
RIP: 0033:0x7f0e62d1a9bf
</TASK>
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffffffffffffffff pfn:0x11ba5f
flags: 0x4000000000000000(zone=1)
raw: 4000000000000000 0000000000000000 00000000ffffffff 0000000000000000
raw: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff88811ba5f480: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff88811ba5f500: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88811ba5f580: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
^
ffff88811ba5f600: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff88811ba5f680: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
Disabling lock debugging due to kernel taint
Opportunistically add a compile time assertion to ensure the maximum number
of sparse banks exactly matches the number of possible bits in the passed
in mask.
[sean: add KASAN splat, drop comment, add assert, massage changelog]
CVSS Score
8.4
EPSS Score
0.001
Published
2026-07-24
In the Linux kernel, the following vulnerability has been resolved:
fpga: region: fix use-after-free in child_regions_with_firmware()
Move of_node_put(child_region) after the error print to avoid accessing
freed memory when pr_err() references child_region.
[ Yilun: Fix the Fixes tag ]
CVSS Score
7.8
EPSS Score
0.002
Published
2026-07-24