KVM: x86: Reject Hyper-V's SEND_IPI hypercalls if local APIC isn't in-kernel
Advertise support for Hyper-V's SEND_IPI and SEND_IPI_EX hypercalls if and
only if the local API is emulated/virtualized by KVM, and explicitly reject
said hypercalls if the local APIC is emulated in userspace, i.e. don't rely
on userspace to opt-in to KVM_CAP_HYPERV_ENFORCE_CPUID.
Rejecting SEND_IPI and SEND_IPI_EX fixes a NULL-pointer dereference if
Hyper-V enlightenments are exposed to the guest without an in-kernel local
APIC:
dump_stack+0xbe/0xfd
__kasan_report.cold+0x34/0x84
kasan_report+0x3a/0x50
__apic_accept_irq+0x3a/0x5c0
kvm_hv_send_ipi.isra.0+0x34e/0x820
kvm_hv_hypercall+0x8d9/0x9d0
kvm_emulate_hypercall+0x506/0x7e0
__vmx_handle_exit+0x283/0xb60
vmx_handle_exit+0x1d/0xd0
vcpu_enter_guest+0x16b0/0x24c0
vcpu_run+0xc0/0x550
kvm_arch_vcpu_ioctl_run+0x170/0x6d0
kvm_vcpu_ioctl+0x413/0xb20
__se_sys_ioctl+0x111/0x160
do_syscal1_64+0x30/0x40
entry_SYSCALL_64_after_hwframe+0x67/0xd1
Note, checking the sending vCPU is sufficient, as the per-VM irqchip_mode
can't be modified after vCPUs are created, i.e. if one vCPU has an
in-kernel local APIC, then all vCPUs have an in-kernel local APIC.
Analysis and contextual insights are available on OpenCVE Cloud.
No vendor fix or workaround currently provided.
Additional remediation guidance may be available on OpenCVE Cloud.
Tracking
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| Source | ID | Title |
|---|---|---|
Debian DLA |
DLA-4102-1 | linux-6.1 security update |
Debian DLA |
DLA-4178-1 | linux security update |
EUVD |
EUVD-2025-5138 | In the Linux kernel, the following vulnerability has been resolved: KVM: x86: Reject Hyper-V's SEND_IPI hypercalls if local APIC isn't in-kernel Advertise support for Hyper-V's SEND_IPI and SEND_IPI_EX hypercalls if and only if the local API is emulated/virtualized by KVM, and explicitly reject said hypercalls if the local APIC is emulated in userspace, i.e. don't rely on userspace to opt-in to KVM_CAP_HYPERV_ENFORCE_CPUID. Rejecting SEND_IPI and SEND_IPI_EX fixes a NULL-pointer dereference if Hyper-V enlightenments are exposed to the guest without an in-kernel local APIC: dump_stack+0xbe/0xfd __kasan_report.cold+0x34/0x84 kasan_report+0x3a/0x50 __apic_accept_irq+0x3a/0x5c0 kvm_hv_send_ipi.isra.0+0x34e/0x820 kvm_hv_hypercall+0x8d9/0x9d0 kvm_emulate_hypercall+0x506/0x7e0 __vmx_handle_exit+0x283/0xb60 vmx_handle_exit+0x1d/0xd0 vcpu_enter_guest+0x16b0/0x24c0 vcpu_run+0xc0/0x550 kvm_arch_vcpu_ioctl_run+0x170/0x6d0 kvm_vcpu_ioctl+0x413/0xb20 __se_sys_ioctl+0x111/0x160 do_syscal1_64+0x30/0x40 entry_SYSCALL_64_after_hwframe+0x67/0xd1 Note, checking the sending vCPU is sufficient, as the per-VM irqchip_mode can't be modified after vCPUs are created, i.e. if one vCPU has an in-kernel local APIC, then all vCPUs have an in-kernel local APIC. |
Ubuntu USN |
USN-7510-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7510-2 | Linux kernel (FIPS) vulnerabilities |
Ubuntu USN |
USN-7510-3 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7510-4 | Linux kernel (Real-time) vulnerabilities |
Ubuntu USN |
USN-7510-5 | Linux kernel (Azure FIPS) vulnerabilities |
Ubuntu USN |
USN-7510-6 | Linux kernel (AWS FIPS) vulnerabilities |
Ubuntu USN |
USN-7510-7 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7510-8 | Linux kernel (AWS) vulnerabilities |
Ubuntu USN |
USN-7511-1 | Linux kernel (GCP) vulnerabilities |
Ubuntu USN |
USN-7511-2 | Linux kernel (GCP FIPS) vulnerabilities |
Ubuntu USN |
USN-7511-3 | Linux kernel (GKE) vulnerabilities |
Ubuntu USN |
USN-7512-1 | Linux kernel (GCP) vulnerabilities |
Ubuntu USN |
USN-7521-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7521-2 | Linux kernel (AWS) vulnerabilities |
Ubuntu USN |
USN-7521-3 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7593-1 | Linux kernel (HWE) vulnerabilities |
Ubuntu USN |
USN-7602-1 | Linux kernel (Xilinx ZynqMP) vulnerabilities |
Ubuntu USN |
USN-7703-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7703-2 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7703-3 | Linux kernel (Oracle) vulnerabilities |
Ubuntu USN |
USN-7703-4 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7719-1 | Linux kernel (Raspberry Pi Real-time) vulnerabilities |
Ubuntu USN |
USN-7737-1 | Linux kernel (Azure) vulnerabilities |
Mon, 03 Nov 2025 21:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| References |
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Mon, 03 Nov 2025 20:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| References |
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Thu, 10 Apr 2025 13:15:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| References |
|
Thu, 13 Mar 2025 13:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.14:rc1:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.14:rc2:*:*:*:*:*:* |
|
| Vendors & Products |
Linux
Linux linux Kernel |
Thu, 13 Mar 2025 12:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| References |
|
Wed, 12 Mar 2025 06:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Weaknesses | CWE-476 |
Fri, 28 Feb 2025 02:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| References |
| |
| Metrics |
threat_severity
|
cvssV3_1
|
Thu, 27 Feb 2025 02:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: KVM: x86: Reject Hyper-V's SEND_IPI hypercalls if local APIC isn't in-kernel Advertise support for Hyper-V's SEND_IPI and SEND_IPI_EX hypercalls if and only if the local API is emulated/virtualized by KVM, and explicitly reject said hypercalls if the local APIC is emulated in userspace, i.e. don't rely on userspace to opt-in to KVM_CAP_HYPERV_ENFORCE_CPUID. Rejecting SEND_IPI and SEND_IPI_EX fixes a NULL-pointer dereference if Hyper-V enlightenments are exposed to the guest without an in-kernel local APIC: dump_stack+0xbe/0xfd __kasan_report.cold+0x34/0x84 kasan_report+0x3a/0x50 __apic_accept_irq+0x3a/0x5c0 kvm_hv_send_ipi.isra.0+0x34e/0x820 kvm_hv_hypercall+0x8d9/0x9d0 kvm_emulate_hypercall+0x506/0x7e0 __vmx_handle_exit+0x283/0xb60 vmx_handle_exit+0x1d/0xd0 vcpu_enter_guest+0x16b0/0x24c0 vcpu_run+0xc0/0x550 kvm_arch_vcpu_ioctl_run+0x170/0x6d0 kvm_vcpu_ioctl+0x413/0xb20 __se_sys_ioctl+0x111/0x160 do_syscal1_64+0x30/0x40 entry_SYSCALL_64_after_hwframe+0x67/0xd1 Note, checking the sending vCPU is sufficient, as the per-VM irqchip_mode can't be modified after vCPUs are created, i.e. if one vCPU has an in-kernel local APIC, then all vCPUs have an in-kernel local APIC. | |
| Title | KVM: x86: Reject Hyper-V's SEND_IPI hypercalls if local APIC isn't in-kernel | |
| References |
|
|
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-05-11T21:06:16.051Z
Reserved: 2024-12-29T08:45:45.764Z
Link: CVE-2025-21779
No data.
Status : Modified
Published: 2025-02-27T03:15:18.690
Modified: 2025-11-03T21:19:09.173
Link: CVE-2025-21779
OpenCVE Enrichment
No data.
Debian DLA
EUVD
Ubuntu USN