CVE-2026-74558
Low risk· EPSS 9%Exploitation Probability (EPSS)
Low risk9th percentile - higher than 9% of all known CVEs
Summary
In the Linux kernel, a vulnerability was found in the XSK zero-copy Tx batch processing path. Invalid descriptors can cause UMEM frame loss or completion ordering violations, leading to incorrect Tx queue behavior.
Risk Assessment
Organizations may experience crashes or hangs in applications using AF_XDP zero-copy, as well as potential memory leaks or improper frame release, which could lead to system instability or DoS attacks.
Recommendation
Apply the official Linux kernel patch for this vulnerability immediately and update the system to a patched version. Monitor distribution security advisories.
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: xsk: reclaim invalid Tx descriptors in ZC batch path The zero-copy Tx batch parser stops when it encounters an invalid descriptor. If this happens after one or more continuation descriptors, the Tx consumer can be advanced past fragments that are neither submitted to the driver nor returned to userspace through the completion ring. A similar problem occurs when a packet exceeds xdp_zc_max_segs. The descriptors consumed up to the limit are released without completion, and the remaining continuation descriptors can subsequently be interpreted as the beginning of another packet. Parse Tx batches in packet units and distinguish descriptors belonging to complete valid packets from descriptors consumed while draining an invalid or oversized packet. Return the former to the driver and append the latter to the CQ address area so userspace can reclaim their UMEM frames. Treat a standalone invalid descriptor as a one-descriptor reclaim-only packet. Advancing the Tx-ring consumer releases the ring slot, but does not by itself return ownership of the referenced UMEM frame to userspace. Once draining starts, continue until the packet's end-of-packet descriptor is consumed. Preserve the drain state on the socket when EOP has not yet been supplied, so draining can continue during a later call. Leave incomplete but otherwise valid packets on the Tx ring. Shared-UMEM pools using multi-buffer Tx also need packet-framed parsing. Walk their Tx sockets one packet at a time, preserving the existing per-socket fairness scheme, instead of using the legacy one-descriptor fallback. Keep that fallback for shared pools that do not use multi-buffer Tx. Since the drain state is maintained per socket and both the singular and shared paths can resume an interrupted drain, changing the socket list from singular to shared requires no special bind-time transition. CQ entries are positional, and drivers may complete only part of the Tx work returned by xsk_tx_peek_release_desc_batch(). Therefore, reclaim-only entries cannot be published immediately when earlier driver-visible descriptors are still outstanding. Track the number of driver-visible CQ entries preceding the reclaim entries. Let xsk_tx_completed() publish partial hardware Tx completions, and publish the reclaim entries only after every earlier Tx descriptor has completed. Complete a reclaim-only batch immediately when there is no driver-visible work in front of it, and prevent another Tx batch from being appended while reclaim entries remain pending. Also cap batch processing by the size of the pool's temporary descriptor array, as Tx rings belonging to sockets sharing a UMEM may have different sizes. This ensures that every invalid Tx descriptor consumed by the ZC batch path is either submitted to the driver as part of a valid packet or returned to userspace without violating CQ completion ordering.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS