CVE-2026-93196
HighCVSS 8.4Exploitation Probability (EPSS)
Low risk6th percentile - higher than 6% of all known CVEs
Summary
A use-after-free vulnerability was found in the Linux kernel's virtio_pmem driver for NVDIMM persistent memory. The issue occurs when a request has already been freed by the submitter but is still reachable via the virtqueue, leading to waking up freed memory during interrupt handling.
Risk Assessment
The vulnerability can cause system crashes (kernel panic) or potentially privilege escalation in virtualized environments using virtio_pmem. However, it requires local access to the guest system.
Recommendation
Apply the Linux kernel patch that introduces reference counting for struct virtio_pmem_request immediately. Update the kernel to a version containing this fix.
Other vulnerabilities in Linux kernel
See all- CVE-2026-99259Unknown
In the Linux kernel, the soc/tegra: pmc driver has an uninitialised early_pmc->rate variable for legacy 32-bit Tegra devices. The variable is never configured and remains 0, triggering a warning in tegra_pmc_enter_suspend_mode(). The issue appeared after the PMC driver was changed to create the PMC context dynamically, updating rate only in the new context.
- CVE-2026-99258Unknown
In the Linux kernel, hv_apicid_to_vp_index() uses per-CPU hypercall input and output pages. In an SEV-SNP CoCo VM without a paravisor the output page is not allocated, so the hypervisor stores the resulting VP index into memory not allocated by the guest. The fix uses the input page for both input and output.
- 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: nvdimm: virtio_pmem: refcount requests for token lifetime KASAN reports slab-use-after-free in __wake_up_common(): BUG: KASAN: slab-use-after-free in __wake_up_common+0x114/0x160 Read of size 8 at addr ffff88810fdcb710 by task swapper/0/0 CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.19.0-next-20260220-00006-g1eae5f204ec3 #4 PREEMPT(full) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Arch Linux 1.17.0-2-2 04/01/2014 Call Trace: <IRQ> dump_stack_lvl+0x6d/0xb0 print_report+0x170/0x4e2 ? __pfx__raw_spin_lock_irqsave+0x10/0x10 ? __virt_addr_valid+0x1dc/0x380 kasan_report+0xbc/0xf0 ? __wake_up_common+0x114/0x160 ? __wake_up_common+0x114/0x160 __wake_up_common+0x114/0x160 ? __pfx__raw_spin_lock_irqsave+0x10/0x10 __wake_up+0x36/0x60 virtio_pmem_host_ack+0x11d/0x3b0 ? sched_balance_domains+0x29f/0xb00 ? __pfx_virtio_pmem_host_ack+0x10/0x10 ? _raw_spin_lock_irqsave+0x98/0x100 ? __pfx__raw_spin_lock_irqsave+0x10/0x10 vring_interrupt+0x1c9/0x5e0 ? __pfx_vp_interrupt+0x10/0x10 vp_vring_interrupt+0x87/0x100 ? __pfx_vp_interrupt+0x10/0x10 __handle_irq_event_percpu+0x17f/0x550 ? __pfx__raw_spin_lock+0x10/0x10 handle_irq_event+0xab/0x1c0 handle_fasteoi_irq+0x276/0xae0 __common_interrupt+0x65/0x130 common_interrupt+0x78/0xa0 </IRQ> virtio_pmem_host_ack() wakes a request that has already been freed by the submitter. This happens when the request token is still reachable via the virtqueue, but virtio_pmem_flush() returns and frees it. Fix the token lifetime by refcounting struct virtio_pmem_request. virtio_pmem_flush() holds a submitter reference, and the virtqueue holds an extra reference once the request is queued. The completion path drops the virtqueue reference, and the submitter drops its reference before returning.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

