Log in Start free

Vulnerability · Published Feb 27, 2025 · Assigned by Linux

CVE-2025-21779KVM: x86: Reject Hyper-V's SEND_IPI hypercalls if local APIC isn't in-kernel

Medium 5.5

In plain English

A medium-severity security flaw in Linux from Linux. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 17% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS NVD)5.5Medium
Exploit odds (30 days)0.3%top 83.4% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official 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.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Debian:12linux6.1.129-1DEBIAN-CVE-2025-21779
Debian:13linux6.12.16-1DEBIAN-CVE-2025-21779
Debian:14linux6.12.16-1DEBIAN-CVE-2025-21779
Ubuntu:22.04:LTSlinux5.15.0-140.150UBUNTU-CVE-2025-21779
Ubuntu:24.04:LTSlinux6.8.0-78.78USN-7703-1
Ubuntu:24.04:LTSlinux6.8.0-78.78UBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-allwinner-5.19no fix listedUBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-aws5.15.0-1084.91UBUNTU-CVE-2025-21779
Ubuntu:24.04:LTSlinux-aws6.8.0-1035.37USN-7703-1
Ubuntu:24.04:LTSlinux-aws6.8.0-1035.37UBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-aws-5.19no fix listedUBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-aws-6.2no fix listedUBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-aws-6.5no fix listedUBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-aws-6.86.8.0-1035.37~22.04.1UBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-aws-6.86.8.0-1035.37~22.04.1USN-7703-2
Ubuntu:22.04:LTSlinux-azure5.15.0-1089.98UBUNTU-CVE-2025-21779
Ubuntu:24.04:LTSlinux-azure6.8.0-1034.39UBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-azure-5.19no fix listedUBUNTU-CVE-2025-21779
Ubuntu:24.04:LTSlinux-azure-6.116.11.0-1015.15~24.04.1UBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-azure-6.2no fix listedUBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-azure-6.5no fix listedUBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-azure-6.86.8.0-1034.39~22.04.1UBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-azure-fde5.15.0-1089.98.1UBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-azure-fde-5.19no fix listedUBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-azure-fde-6.2no fix listedUBUNTU-CVE-2025-21779
Ubuntu:24.04:LTSlinux-azure-nvidia6.8.0-1022.23UBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-gcp5.15.0-1083.92UBUNTU-CVE-2025-21779
Ubuntu:24.04:LTSlinux-gcp6.8.0-1036.38USN-7703-2
Ubuntu:24.04:LTSlinux-gcp6.8.0-1036.38UBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-gcp-5.19no fix listedUBUNTU-CVE-2025-21779
Ubuntu:24.04:LTSlinux-gcp-6.116.11.0-1015.15~24.04.1UBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-gcp-6.2no fix listedUBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-gcp-6.5no fix listedUBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-gcp-6.86.8.0-1036.38~22.04.1USN-7703-2
Ubuntu:22.04:LTSlinux-gcp-6.86.8.0-1036.38~22.04.1UBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-gke5.15.0-1081.87UBUNTU-CVE-2025-21779
Ubuntu:24.04:LTSlinux-gke6.8.0-1032.36UBUNTU-CVE-2025-21779
Ubuntu:24.04:LTSlinux-gke6.8.0-1032.36USN-7703-4
Ubuntu:22.04:LTSlinux-gkeop5.15.0-1066.74UBUNTU-CVE-2025-21779
Ubuntu:24.04:LTSlinux-gkeop6.8.0-1019.21USN-7703-2
Ubuntu:24.04:LTSlinux-gkeop6.8.0-1019.21UBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-hwe-5.19no fix listedUBUNTU-CVE-2025-21779
Ubuntu:24.04:LTSlinux-hwe-6.116.11.0-26.26~24.04.1UBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-hwe-6.2no fix listedUBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-hwe-6.5no fix listedUBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-hwe-6.86.8.0-78.78~22.04.1USN-7703-4
Ubuntu:22.04:LTSlinux-hwe-6.86.8.0-78.78~22.04.1UBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-ibm5.15.0-1076.79UBUNTU-CVE-2025-21779
Ubuntu:24.04:LTSlinux-ibm6.8.0-1033.33USN-7703-2
Ubuntu:24.04:LTSlinux-ibm6.8.0-1033.33UBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-ibm-6.86.8.0-1033.33~22.04.1UBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-ibm-6.86.8.0-1033.33~22.04.1USN-7703-2
Ubuntu:24.04:LTSlinux-intelno fix listedUBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-intel-iot-realtimeno fix listedUBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-intel-iotg5.15.0-1079.85UBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-kvm5.15.0-1080.85UBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-lowlatency5.15.0-140.150UBUNTU-CVE-2025-21779
Ubuntu:24.04:LTSlinux-lowlatency6.8.0-78.78.1USN-7703-1
Ubuntu:24.04:LTSlinux-lowlatency6.8.0-78.78.1UBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-lowlatency-hwe-5.19no fix listedUBUNTU-CVE-2025-21779
Ubuntu:24.04:LTSlinux-lowlatency-hwe-6.116.11.0-1014.15~24.04.1UBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-lowlatency-hwe-6.2no fix listedUBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-lowlatency-hwe-6.5no fix listedUBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-lowlatency-hwe-6.86.8.0-78.78.1~22.04.1USN-7703-1
Ubuntu:22.04:LTSlinux-lowlatency-hwe-6.86.8.0-78.78.1~22.04.1UBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-nvidia5.15.0-1078.79UBUNTU-CVE-2025-21779
Ubuntu:24.04:LTSlinux-nvidia6.8.0-1035.38USN-7703-4
Ubuntu:24.04:LTSlinux-nvidia6.8.0-1035.38UBUNTU-CVE-2025-21779
Ubuntu:24.04:LTSlinux-nvidia-6.116.11.0-1010.10UBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-nvidia-6.2no fix listedUBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-nvidia-6.5no fix listedUBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-nvidia-6.86.8.0-1035.38~22.04.1UBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-nvidia-6.86.8.0-1035.38~22.04.1USN-7703-4
Ubuntu:24.04:LTSlinux-nvidia-lowlatency6.8.0-1035.38.1USN-7703-4
Ubuntu:24.04:LTSlinux-nvidia-lowlatency6.8.0-1035.38.1UBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-nvidia-tegra5.15.0-1037.37UBUNTU-CVE-2025-21779
Ubuntu:24.04:LTSlinux-nvidia-tegra6.8.0-1009.9UBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-nvidia-tegra-igx5.15.0-1026.26UBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-oem-5.17no fix listedUBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-oem-6.0no fix listedUBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-oem-6.1no fix listedUBUNTU-CVE-2025-21779
Ubuntu:24.04:LTSlinux-oem-6.116.11.0-1022.22UBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-oem-6.5no fix listedUBUNTU-CVE-2025-21779
Ubuntu:24.04:LTSlinux-oem-6.8no fix listedUBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-oracle5.15.0-1081.87UBUNTU-CVE-2025-21779
Ubuntu:24.04:LTSlinux-oracle6.8.0-1032.33UBUNTU-CVE-2025-21779
Ubuntu:24.04:LTSlinux-oracle6.8.0-1032.33USN-7703-3
Ubuntu:22.04:LTSlinux-oracle-6.5no fix listedUBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-oracle-6.86.8.0-1032.33~22.04.1USN-7703-3
Ubuntu:22.04:LTSlinux-oracle-6.86.8.0-1032.33~22.04.1UBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-raspi5.15.0-1078.81UBUNTU-CVE-2025-21779
Ubuntu:24.04:LTSlinux-raspi6.8.0-1035.39UBUNTU-CVE-2025-21779
Ubuntu:24.04:LTSlinux-raspi6.8.0-1035.39USN-7703-4
Ubuntu:24.04:LTSlinux-raspi-realtimeno fix listedUBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-realtimeno fix listedUBUNTU-CVE-2025-21779
Ubuntu:24.04:LTSlinux-realtimeno fix listedUBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-riscvno fix listedUBUNTU-CVE-2025-21779
Ubuntu:24.04:LTSlinux-riscvno fix listedUBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-riscv-5.19no fix listedUBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-riscv-6.5no fix listedUBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-riscv-6.86.8.0-78.78~22.04.1UBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-starfive-5.19no fix listedUBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-starfive-6.2no fix listedUBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-starfive-6.5no fix listedUBUNTU-CVE-2025-21779
Ubuntu:24.04:LTSlinux-xilinx6.8.0-1017.18UBUNTU-CVE-2025-21779
Ubuntu:22.04:LTSlinux-xilinx-zynqmp5.15.0-1050.54UBUNTU-CVE-2025-21779

Affected products (as reported)

VendorProductVersions
Linux Linux 214ff83d4473a7757fa18a64dc7efe3b0e158486 – before 61224533f2b61e252b03e214195d27d64b22989a214ff83d4473a7757fa18a64dc7efe3b0e158486 – before 45fa526b0f5a34492ed0536c3cdf88b78380e4de214ff83d4473a7757fa18a64dc7efe3b0e158486 – before 5393cf22312418262679eaadb130d608c75fe690214ff83d4473a7757fa18a64dc7efe3b0e158486 – before 874ff13c73c45ecb38cb82191e8c1d523f0dc81b214ff83d4473a7757fa18a64dc7efe3b0e158486 – before aca8be4403fb90db7adaf63830e27ebe787a76e8214ff83d4473a7757fa18a64dc7efe3b0e158486 – before ca29f58ca374c40a0e69c5306fc5c940a0069074214ff83d4473a7757fa18a64dc7efe3b0e158486 – before a8de7f100bb5989d9c3627d3a223ee1c863f3b69
Linux Linux 4.20

References