CVE-2023-53319 KVM: arm64: Handle kvm_arm_init failure correctly in finalize_pkvm

Medium 5.5 Published 16 Sep 2025 Updated 11 May 2026

A race condition in Linux kernel KVM initialization can cause a kernel panic and system crash if hypervisor initialization fails.

Exploited in the wild: Not known
Login needed: Any signed-in user
Attackable: Local or same network only
Victim action needed: Not needed
Fix: Available

What is CVE-2023-53319?

CVE-2023-53319 is a medium-severity denial of service vulnerability in Linux kernel, published on 16 Sep 2025. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

In the Linux kernel, the following vulnerability has been resolved:

KVM: arm64: Handle kvm_arm_init failure correctly in finalize_pkvm

Currently there is no synchronisation between finalize_pkvm() and kvm_arm_init() initcalls. The finalize_pkvm() proceeds happily even if kvm_arm_init() fails resulting in the following warning on all the CPUs and eventually a HYP panic:

| kvm [1]: IPA Size Limit: 48 bits | kvm [1]: Failed to init hyp memory protection | kvm [1]: error initializing Hyp mode: -22 | | <snip> | | WARNING: CPU: 0 PID: 0 at arch/arm64/kvm/pkvm.c:226 _kvm_host_prot_finalize+0x30/0x50 | Modules linked in: | CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.4.0 #237 | Hardware name: FVP Base RevC (DT) | pstate: 634020c5 (nZCv daIF +PAN -UAO +TCO +DIT -SSBS BTYPE=--) | pc : _kvm_host_prot_finalize+0x30/0x50 | lr : __flush_smp_call_function_queue+0xd8/0x230 | | Call trace: | _kvm_host_prot_finalize+0x3c/0x50 | on_each_cpu_cond_mask+0x3c/0x6c | pkvm_drop_host_privileges+0x4c/0x78 | finalize_pkvm+0x3c/0x5c | do_one_initcall+0xcc/0x240 | do_initcall_level+0x8c/0xac | do_initcalls+0x54/0x94 | do_basic_setup+0x1c/0x28 | kernel_init_freeable+0x100/0x16c | kernel_init+0x20/0x1a0 | ret_from_fork+0x10/0x20 | Failed to finalize Hyp protection: -22 | dtb=fvp-base-revc.dtb | kvm [95]: nVHE hyp BUG at: arch/arm64/kvm/hyp/nvhe/mem_protect.c:540! | kvm [95]: nVHE call trace: | kvm [95]: [<ffff800081052984>] __kvm_nvhe_hyp_panic+0xac/0xf8 | kvm [95]: [<ffff800081059644>] __kvm_nvhe_handle_host_mem_abort+0x1a0/0x2ac | kvm [95]: [<ffff80008105511c>] __kvm_nvhe_handle_trap+0x4c/0x160 | kvm [95]: [<ffff8000810540fc>] __kvm_nvhe___skip_pauth_save+0x4/0x4 | kvm [95]: ---[ end nVHE call trace ]--- | kvm [95]: Hyp Offset: 0xfffe8db00ffa0000 | Kernel panic - not syncing: HYP panic: | PS:a34023c9 PC:0000f250710b973c ESR:00000000f2000800 | FAR:ffff000800cb00d0 HPFAR:000000000880cb00 PAR:0000000000000000 | VCPU:0000000000000000 | CPU: 3 PID: 95 Comm: kworker/u16:2 Tainted: G W 6.4.0 #237 | Hardware name: FVP Base RevC (DT) | Workqueue: rpciod rpc_async_schedule | Call trace: | dump_backtrace+0xec/0x108 | show_stack+0x18/0x2c | dump_stack_lvl+0x50/0x68 | dump_stack+0x18/0x24 | panic+0x138/0x33c | nvhe_hyp_panic_handler+0x100/0x184 | new_slab+0x23c/0x54c | ___slab_alloc+0x3e4/0x770 | kmem_cache_alloc_node+0x1f0/0x278 | __alloc_skb+0xdc/0x294 | tcp_stream_alloc_skb+0x2c/0xf0 | tcp_sendmsg_locked+0x3d0/0xda4 | tcp_sendmsg+0x38/0x5c | inet_sendmsg+0x44/0x60 | sock_sendmsg+0x1c/0x34 | xprt_sock_sendmsg+0xdc/0x274 | xs_tcp_send_request+0x1ac/0x28c | xprt_transmit+0xcc/0x300 | call_transmit+0x78/0x90 | __rpc_execute+0x114/0x3d8 | rpc_async_schedule+0x28/0x48 | process_one_work+0x1d8/0x314 | worker_thread+0x248/0x474 | kthread+0xfc/0x184 | ret_from_fork+0x10/0x20 | SMP: stopping secondary CPUs | Kernel Offset: 0x57c5cb460000 from 0xffff800080000000 | PHYS_OFFSET: 0x80000000 | CPU features: 0x00000000,1035b7a3,ccfe773f | Memory Limit: none | ---[ end Kernel panic - not syncing: HYP panic: | PS:a34023c9 PC:0000f250710b973c ESR:00000000f2000800 | FAR:ffff000800cb00d0 HPFAR:000000000880cb00 PAR:0000000000000000 | VCPU:0000000000000000 ]---

Fix it by checking for the successfull initialisation of kvm_arm_init() in finalize_pkvm() before proceeding any futher.

Which versions are affected by CVE-2023-53319?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2023-53319?

Apply the vendor's patch.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2023-53319 being exploited?

There is no known exploitation of CVE-2023-53319 in the wild and no public exploit code.

All Linux kernel vulnerabilities

Sources

Also known as BELL-CVE-2023-53319, DEBIAN-CVE-2023-53319, GHSA-cch5-3fv5-qh9h, UBUNTU-CVE-2023-53319.