CVE-2024-26891
MediumCVSS 5.5Exploitation Probability (EPSS)
Low risk13th percentile - higher than 13% of all known CVEs
Summary
A flaw in the Linux kernel's IOMMU VT-d handling causes an ATS (Address Translation Services) invalidation request to be sent to a device that has already been disconnected (e.g., via hotplug). This triggers an infinite retry loop in interrupt context, leading to a hard lockup and kernel panic.
Risk Assessment
Organizations using servers with PCIe hotplug support and Intel VT-d enabled may experience sudden system hangs or kernel panics when devices are removed, resulting in service unavailability and potential data loss.
Recommendation
Update the Linux kernel to a version containing the fix for CVE-2024-26891. If immediate update is not possible, consider disabling hotplug on PCIe ports or limiting Intel VT-d usage to essential cases.
Other vulnerabilities in Linux kernel
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- CVE-2026-99258Unknown
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- CVE-2026-99257Unknown
In the Linux kernel, the shared GPIO mechanism based on platform lookup tables requires an associated struct device. An fwnode-based lookup with no associated device currently causes a NULL-pointer dereference. The fix adds a check that lets the kernel gracefully handle this situation with an error.
- CVE-2026-99256Unknown
In the Linux kernel, the dm cache module used a rw_semaphore for background_work_lock, although write locks on rw_semaphores have strict owner semantics. The locking process was not always the same as the unlocking one, triggering a warning with CONFIG_DEBUG_RWSEMS during suspend/resume of a cache device. The fix replaces the rw_semaphore with a spinlock and a wait queue.
- CVE-2026-99251Unknown
In the Linux kernel, init_vp_index() contains a retry loop that strips CPUs from a node if they are already in the allocated cpumask or outside the HK_TYPE_MANAGED_IRQ housekeeping cpumask. If the housekeeping cpumask contains no CPU in that node, the loop becomes infinite. The fix skips NUMA nodes with no housekeeping CPU and aborts early when no online housekeeping CPUs exist.
- CVE-2026-99250Unknown
In the Linux kernel, the NBCON console printing kthreads are started very early during boot via early_initcall(). Asynchronously enabling/disabling interrupts during early boot may interfere with early SMP setup on some hardware platforms, causing hangs. The fix postpones kthread startup until after all arch initcalls have completed.
- CVE-2026-99249Unknown
In the Linux kernel, zap_pid_ns_processes() waiting for PID namespace cleanup was not freezable. A tracer outside the namespace that does not reap its traced zombies keeps PIDs allocated, making the wait unbounded and causing every suspend attempt to fail. The fix makes the wait loops use TASK_FREEZABLE states so the freezer can freeze waiting tasks.
- CVE-2026-99248Unknown
In the Linux kernel, the i2c: xiic driver was changed to restore non-managed runtime PM instead of the devres-based approach to fix a clk WARN flood. The managed release tore down runtime PM in the wrong order, causing the clock to be disabled twice and triggering "clkN already disabled" warnings on every teardown.
- CVE-2026-99247Unknown
In the Linux kernel, if trace buffer allocation fails during early boot, tracing_disabled remains set and the global trace array events list stays uninitialized. tracer_init_tracefs_work_func() runs asynchronously without checking this state and calls event_trace_init() and init_tracer_tracefs(), leading to a NULL pointer dereference Oops during boot. The fix checks tracing_disabled at the start of the work function.
- CVE-2026-99215Unknown
In the Linux kernel power supply subsystem, a use-after-free vulnerability exists. If a power supply is unregistered while its external_power_changed() callback is still running, the driver may free data that the callback is still accessing, leading to a kernel crash (NULL pointer dereference).
Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: iommu/vt-d: Don't issue ATS Invalidation request when device is disconnected For those endpoint devices connect to system via hotplug capable ports, users could request a hot reset to the device by flapping device's link through setting the slot's link control register, as pciehp_ist() DLLSC interrupt sequence response, pciehp will unload the device driver and then power it off. thus cause an IOMMU device-TLB invalidation (Intel VT-d spec, or ATS Invalidation in PCIe spec r6.1) request for non-existence target device to be sent and deadly loop to retry that request after ITE fault triggered in interrupt context. That would cause following continuous hard lockup warning and system hang [ 4211.433662] pcieport 0000:17:01.0: pciehp: Slot(108): Link Down [ 4211.433664] pcieport 0000:17:01.0: pciehp: Slot(108): Card not present [ 4223.822591] NMI watchdog: Watchdog detected hard LOCKUP on cpu 144 [ 4223.822622] CPU: 144 PID: 1422 Comm: irq/57-pciehp Kdump: loaded Tainted: G S OE kernel version xxxx [ 4223.822623] Hardware name: vendorname xxxx 666-106, BIOS 01.01.02.03.01 05/15/2023 [ 4223.822623] RIP: 0010:qi_submit_sync+0x2c0/0x490 [ 4223.822624] Code: 48 be 00 00 00 00 00 08 00 00 49 85 74 24 20 0f 95 c1 48 8b 57 10 83 c1 04 83 3c 1a 03 0f 84 a2 01 00 00 49 8b 04 24 8b 70 34 <40> f6 c6 1 0 74 17 49 8b 04 24 8b 80 80 00 00 00 89 c2 d3 fa 41 39 [ 4223.822624] RSP: 0018:ffffc4f074f0bbb8 EFLAGS: 00000093 [ 4223.822625] RAX: ffffc4f040059000 RBX: 0000000000000014 RCX: 0000000000000005 [ 4223.822625] RDX: ffff9f3841315800 RSI: 0000000000000000 RDI: ffff9f38401a8340 [ 4223.822625] RBP: ffff9f38401a8340 R08: ffffc4f074f0bc00 R09: 0000000000000000 [ 4223.822626] R10: 0000000000000010 R11: 0000000000000018 R12: ffff9f384005e200 [ 4223.822626] R13: 0000000000000004 R14: 0000000000000046 R15: 0000000000000004 [ 4223.822626] FS: 0000000000000000(0000) GS:ffffa237ae400000(0000) knlGS:0000000000000000 [ 4223.822627] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 4223.822627] CR2: 00007ffe86515d80 CR3: 000002fd3000a001 CR4: 0000000000770ee0 [ 4223.822627] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 4223.822628] DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 0000000000000400 [ 4223.822628] PKRU: 55555554 [ 4223.822628] Call Trace: [ 4223.822628] qi_flush_dev_iotlb+0xb1/0xd0 [ 4223.822628] __dmar_remove_one_dev_info+0x224/0x250 [ 4223.822629] dmar_remove_one_dev_info+0x3e/0x50 [ 4223.822629] intel_iommu_release_device+0x1f/0x30 [ 4223.822629] iommu_release_device+0x33/0x60 [ 4223.822629] iommu_bus_notifier+0x7f/0x90 [ 4223.822630] blocking_notifier_call_chain+0x60/0x90 [ 4223.822630] device_del+0x2e5/0x420 [ 4223.822630] pci_remove_bus_device+0x70/0x110 [ 4223.822630] pciehp_unconfigure_device+0x7c/0x130 [ 4223.822631] pciehp_disable_slot+0x6b/0x100 [ 4223.822631] pciehp_handle_presence_or_link_change+0xd8/0x320 [ 4223.822631] pciehp_ist+0x176/0x180 [ 4223.822631] ? irq_finalize_oneshot.part.50+0x110/0x110 [ 4223.822632] irq_thread_fn+0x19/0x50 [ 4223.822632] irq_thread+0x104/0x190 [ 4223.822632] ? irq_forced_thread_fn+0x90/0x90 [ 4223.822632] ? irq_thread_check_affinity+0xe0/0xe0 [ 4223.822633] kthread+0x114/0x130 [ 4223.822633] ? __kthread_cancel_work+0x40/0x40 [ 4223.822633] ret_from_fork+0x1f/0x30 [ 4223.822633] Kernel panic - not syncing: Hard LOCKUP [ 4223.822634] CPU: 144 PID: 1422 Comm: irq/57-pciehp Kdump: loaded Tainted: G S OE kernel version xxxx [ 4223.822634] Hardware name: vendorname xxxx 666-106, BIOS 01.01.02.03.01 05/15/2023 [ 4223.822634] Call Trace: [ 4223.822634] <NMI> [ 4223.822635] dump_stack+0x6d/0x88 [ 4223.822635] panic+0x101/0x2d0 [ 4223.822635] ? ret_from_fork+0x11/0x30 [ 4223.822635] nmi_panic.cold.14+0xc/0xc [ 4223.822636] watchdog_overflow_callback.cold.8+0x6d/0x81 [ 4223.822636] __perf_event_overflow+0x4f/0xf0 [ 4223.822636] handle_pmi_common ---truncated---
Vulnerability data from NVD (NIST) · CISA KEV · EPSS