CVE-2026-80739
Low risk· EPSS 6%Exploitation Probability (EPSS)
Low risk6th percentile - higher than 6% of all known CVEs
Summary
In the Linux kernel, a vulnerability in the mlx5e driver (for Mellanox/NVIDIA network cards) leads to a deadlock (AA deadlock). The issue occurs when an FDB flow addition in TC fails at lower levels, and then flow deletion (mlx5e_tc_del_flow) tries to acquire the devcom lock again, which is already held for peer flows. This causes recursive locking (lockdep: possible recursive locking detected).
Risk Assessment
The deadlock can cause the system or network driver to hang, resulting in network interface unavailability and potential disruption of network services in production environments.
Recommendation
Apply a Linux kernel update containing the fix (introducing a PEER flag and checking it before acquiring the devcom lock). If not possible, restrict the use of TC flower on mlx5e interfaces until the patch is deployed.
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: net/mlx5e: TC, Check if flow is PEER before acquiring devcom lock In case __mlx5e_add_fdb_flow() fails in lower levels, the flow is deleted via mlx5e_tc_del_flow(), and mlx5e_tc_del_flow() is acquiring ESW devcom lock without condition. In addition, in case of peer_flow, __mlx5e_add_fdb_flow() is called while holding ESW devcom comp lock. This results in an AA deadlock. To fix this, introduce a new PEER flag that is set on flows created as peer flows (the duplicate flows on peer devices), and check it in mlx5e_tc_del_flow() before acquiring ESW devcom lock. Lockdep splat: ============================================ WARNING: possible recursive locking detected ============================================ Possible unsafe locking scenario: CPU0 ---- lock(&comp->lock_key#2); lock(&comp->lock_key#2); *** DEADLOCK *** Call Trace: <TASK> dump_stack_lvl+0x69/0xa0 print_deadlock_bug.cold+0xbd/0xca __lock_acquire+0x1671/0x2ec0 lock_acquire+0x10e/0x2e0 down_read+0x95/0x430 mlx5_devcom_for_each_peer_begin+0x4e/0xe0 [mlx5_core] mlx5e_tc_del_flow+0x11d/0xa70 [mlx5_core] mlx5e_flow_put+0x99/0x100 [mlx5_core] __mlx5e_add_fdb_flow+0x409/0xf00 [mlx5_core] mlx5e_configure_flower+0x2a86/0x4100 [mlx5_core] mlx5e_rep_setup_tc_cls_flower+0x12f/0x1b0 [mlx5_core] mlx5e_rep_setup_tc_cb+0x153/0x750 [mlx5_core] tc_setup_cb_add+0x1dc/0x470 fl_change+0x2f4d/0x626d [cls_flower] tc_new_tfilter+0x79b/0x2310 rtnetlink_rcv_msg+0x778/0xad0 do_syscall_64+0x70/0x960 entry_SYSCALL_64_after_hwframe+0x4b/0x53 </TASK>
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

