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Unscored CVE-2026-98713 EUVD-2026-103967GHSA-854r-xw42-gj8x

KVM: arm64: Apply the fine-grained UNDEFs without FEAT_FGT

Published Oct 18, 2026 · Updated Oct 19, 2026 · Assigned by Linux

Vendor: Linux Product: Linux Package: linux Package: linux Package: linux-6.12 Package: linux-allwinner-5.19 Package: linux-aws Package: linux-aws-5.0 Package: linux-aws-5.11 Package: linux-aws-5.13 Package: linux-aws-5.19 Package: linux-aws-5.3 Package: linux-aws-5.8 Package: linux-aws-6.14 Package: linux-aws-6.17 Package: linux-aws-6.2 Package: linux-aws-6.5 Package: linux-aws-7.0 Package: linux-azure Package: linux-azure-5.11 Package: linux-azure-5.13 Package: linux-azure-5.19 Package: linux-azure-5.3 Package: linux-azure-5.8 Package: linux-azure-6.11 Package: linux-azure-6.14 Package: linux-azure-6.17 Package: linux-azure-6.2 Package: linux-azure-6.5 Package: linux-azure-7.0 Package: linux-azure-edge Package: linux-azure-fde Package: linux-azure-fde-5.19 Package: linux-azure-fde-6.14 Package: linux-azure-fde-6.17 Package: linux-azure-fde-6.2 Package: linux-azure-fde-7.0 Package: linux-azure-nvidia-6.14 Package: linux-gcp Package: linux-gcp-5.11 Package: linux-gcp-5.13 Package: linux-gcp-5.19 Package: linux-gcp-5.3 Package: linux-gcp-5.8 Package: linux-gcp-6.11 Package: linux-gcp-6.14 Package: linux-gcp-6.17 Package: linux-gcp-6.2 Package: linux-gcp-6.5 Package: linux-gcp-7.0 Package: linux-gke Package: linux-gke-4.15 Package: linux-gke-5.15 Package: linux-gke-5.4 Package: linux-gkeop Package: linux-gkeop-5.15 Package: linux-gkeop-5.4 Package: linux-hwe Package: linux-hwe-5.11 Package: linux-hwe-5.13 Package: linux-hwe-5.19 Package: linux-hwe-5.8 Package: linux-hwe-6.11 Package: linux-hwe-6.14 Package: linux-hwe-6.17 Package: linux-hwe-6.2 Package: linux-hwe-6.5 Package: linux-hwe-7.0 Package: linux-hwe-edge Package: linux-ibm Package: linux-intel-5.13 Package: linux-intel-iot-realtime Package: linux-lowlatency-hwe-5.19 Package: linux-lowlatency-hwe-6.11 Package: linux-lowlatency-hwe-6.2 Package: linux-lowlatency-hwe-6.5 Package: linux-nvidia Package: linux-nvidia-6.11 Package: linux-nvidia-6.17 Package: linux-nvidia-6.2 Package: linux-nvidia-6.5 Package: linux-nvidia-7.0 Package: linux-nvidia-bos Package: linux-oem Package: linux-oem-5.10 Package: linux-oem-5.13 Package: linux-oem-5.14 Package: linux-oem-5.17 Package: linux-oem-5.6 Package: linux-oem-6.0 Package: linux-oem-6.1 Package: linux-oem-6.11 Package: linux-oem-6.14 Package: linux-oem-6.17 Package: linux-oem-6.5 Package: linux-oem-6.8 Package: linux-oem-7.0 Package: linux-oracle Package: linux-oracle-5.0 Package: linux-oracle-5.11 Package: linux-oracle-5.13 Package: linux-oracle-5.3 Package: linux-oracle-5.8 Package: linux-oracle-6.14 Package: linux-oracle-6.17 Package: linux-oracle-6.5 Package: linux-oracle-7.0 Package: linux-raspi Package: linux-raspi-realtime Package: linux-raspi2 Package: linux-realtime Package: linux-realtime-6.14 Package: linux-realtime-6.17 Package: linux-riscv Package: linux-riscv-5.11 Package: linux-riscv-5.19 Package: linux-riscv-5.8 Package: linux-riscv-6.14 Package: linux-riscv-6.17 Package: linux-riscv-6.5 Package: linux-riscv-7.0 Package: linux-starfive-5.19 Package: linux-starfive-6.2 Package: linux-starfive-6.5 Package: linux-vmware Platform: Linux Ecosystem: Debian Ecosystem: Ubuntu

Description

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

KVM: arm64: Apply the fine-grained UNDEFs without FEAT_FGT

FGUs don't actually require hardware support, so don't gate fgt trap
config insertion on FGT. This is the only action required to allow FGUs
always, as kvm_calculate_traps() already computes the FGU bits with or
without FEAT_FGT.

This also fixes a spurious WARN when a TLBI OS is run on a guest in vEL1
without FEAT_TLBIOS on non FEAT_FGT hardware. In this configuration the
course-grained HCR_EL2.TTLBOS trap reaches the handler handle_tlbi_el1(),
which expects an EL1 TLBI only from vEL2. With FGUs enabled the UNDEF
will be injected without needing the specific handler.

[oliver: Take Wei-Lin's suggested changelog]

Affected products

VendorProductAffectedFixed
Linux Linux 6.9 6.12.113

Fixed in Linux distributions

Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.

ReleasePackageFixed inAdvisory
Debian 14 linux 7.2.10-1 —
Debian 13 linux 6.12.113-1 —
Debian 12 linux-6.12 6.12.113-1~deb12u1 —
ReleasePackageFixed inAdvisory
Ubuntu 26.04 LTS linux 7.0.0-43.43 USN-9018-1
Ubuntu 26.04 LTS linux-aws 7.0.0-1017.18 USN-9018-1
Ubuntu 26.04 LTS linux-azure 7.0.0-1020.21 USN-9019-1
Ubuntu 26.04 LTS linux-azure-fde 7.0.0-1019.19 USN-9020-1
Ubuntu 26.04 LTS linux-gcp 7.0.0-1017.19 USN-9018-1
Ubuntu 26.04 LTS linux-gke 7.0.0-1010.11 USN-9020-1
Ubuntu 26.04 LTS linux-ibm +1 7.0.0-1018.18 USN-9018-1
Ubuntu 26.04 LTS linux-oracle 7.0.0-1016.18 USN-9018-1
Ubuntu 26.04 LTS linux-raspi 7.0.0-1023.23 USN-9021-1
Ubuntu 26.04 LTS linux-realtime 7.0.0-43.43.1 USN-9020-1
Ubuntu 26.04 LTS linux-riscv +2 No fix yet —
Ubuntu 24.04 LTS linux-aws-7.0 7.0.0-1017.18~24.04.1 USN-9020-1
Ubuntu 24.04 LTS linux-azure-fde-7.0 7.0.0-1019.19~24.04.1 USN-9020-1
Ubuntu 24.04 LTS linux-gcp-7.0 7.0.0-1017.19~24.04.1 USN-9020-1
Ubuntu 24.04 LTS linux-hwe-7.0 7.0.0-43.43~24.04.1 USN-9018-2
Ubuntu 24.04 LTS linux-oracle-7.0 7.0.0-1016.18~24.04.1 USN-9020-1
Ubuntu 24.04 LTS linux-riscv +29 No fix yet —
Ubuntu 24.04 LTS linux-riscv-7.0 7.0.0-43.43.1~24.04.2 —
Ubuntu 22.04 LTS linux-riscv +32 No fix yet —
Ubuntu 20.04 LTS linux-gke +28 No fix yet —
Ubuntu 18.04 LTS linux-gcp +14 No fix yet —
Show 2 more (older releases, extended support, other products)
ReleasePackageFixed inAdvisory
Ubuntu 16.04 LTS linux-hwe-edge No fix yet —
Ubuntu Pro Realtime 24.04 LTS linux-realtime-6.14 +1 No fix yet —
ReleasePackageFixed inAdvisory
SLES for SAP 16.0 kernel-64kb +8 6.12.0-160000.41.1 SUSE-SU-2026:24662-1
SLES for SAP 16.0 kernel-default-base 6.12.0-160000.41.1.160000.2.32 SUSE-SU-2026:24662-1
SLES 16.0 kernel-64kb +8 6.12.0-160000.41.1 SUSE-SU-2026:24662-1, SUSE-SU-2026:24651-1
SLES 16.0 kernel-default-base 6.12.0-160000.41.1.160000.2.32 SUSE-SU-2026:24662-1
SLE Micro 6.2 kernel-default-base 6.12.0-160000.41.1.160000.2.32 SUSE-SU-2026:24643-1
SLE Micro 6.2 kernel-rt +5 6.12.0-160000.41.1 SUSE-SU-2026:24648-1, SUSE-SU-2026:24643-1

Amazon Linux

ReleasePackageFixed inAdvisory
Amazon Linux 2023 kernel-livepatch-6.18.56-125.164 +1 1:1.0-0.amzn2023 ALAS2023-2026-3335, ALAS2023-2026-3251
Amazon Linux 2023 perf6.12 +11 1:6.12.113-138.209.amzn2023 ALAS2023-2026-3335
Amazon Linux 2023 perf6.18 +12 1:6.18.56-125.164.amzn2023 ALAS2023-2026-3251

Advisories 12

References