CVE-2026-23005
published 2026-01-25CVE-2026-23005: In the Linux kernel, the following vulnerability has been resolved: x86/fpu: Clear XSTATE_BV[i] in guest XSAVE state whenever XFD[i]=1 When loading guest XSAVE…
PriorityP421medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.20%
9.9th percentile
In the Linux kernel, the following vulnerability has been resolved:
x86/fpu: Clear XSTATE_BV[i] in guest XSAVE state whenever XFD[i]=1
When loading guest XSAVE state via KVM_SET_XSAVE, and when updating XFD in
response to a guest WRMSR, clear XFD-disabled features in the saved (or to
be restored) XSTATE_BV to ensure KVM doesn't attempt to load state for
features that are disabled via the guest's XFD. Because the kernel
executes XRSTOR with the guest's XFD, saving XSTATE_BV[i]=1 with XFD[i]=1
will cause XRSTOR to #NM and panic the kernel.
E.g. if fpu_update_guest_xfd() sets XFD without clearing XSTATE_BV:
------------[ cut here ]------------
WARNING: arch/x86/kernel/traps.c:1524 at exc_device_not_available+0x101/0x110, CPU#29: amx_test/848
Modules linked in: kvm_intel kvm irqbypass
CPU: 29 UID: 1000 PID: 848 Comm: amx_test Not tainted 6.19.0-rc2-ffa07f7fd437-x86_amx_nm_xfd_non_init-vm #171 NONE
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
RIP: 0010:exc_device_not_available+0x101/0x110
Call Trace:
asm_exc_device_not_available+0x1a/0x20
RIP: 0010:restore_fpregs_from_fpstate+0x36/0x90
switch_fpu_return+0x4a/0xb0
kvm_arch_vcpu_ioctl_run+0x1245/0x1e40 [kvm]
kvm_vcpu_ioctl+0x2c3/0x8f0 [kvm]
__x64_sys_ioctl+0x8f/0xd0
do_syscall_64+0x62/0x940
entry_SYSCALL_64_after_hwframe+0x4b/0x53
---[ end trace 0000000000000000 ]---
This can happen if the guest executes WRMSR(MSR_IA32_XFD) to set XFD[18] = 1,
and a host IRQ triggers kernel_fpu_begin() prior to the vmexit handler's
call to fpu_update_guest_xfd().
and if userspace stuffs XSTATE_BV[i]=1 via KVM_SET_XSAVE:
------------[ cut here ]------------
WARNING: arch/x86/kernel/traps.c:1524 at exc_device_not_available+0x101/0x110, CPU#14: amx_test/867
Modules linked in: kvm_intel kvm irqbypass
CPU: 14 UID: 1000 PID: 867 Comm: amx_test Not tainted 6.19.0-rc2-2dace9faccd6-x86_amx_nm_xfd_non_init-vm #168 NONE
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
RIP: 0010:exc_device
Affected
58 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 6.1.162-1 (bookworm) | linux 6.1.162-1 (bookworm) |
| debian | linux-6.1 | < linux 6.1.162-1 (bookworm) | linux 6.1.162-1 (bookworm) |
| linux | linux | — | — |
| linux | linux | >= 820a6ee944e74e57255ac2e90916ecdaade57b95 < b5995c01ba53d84182ecb9492fc4d91cfe8a362d | b5995c01ba53d84182ecb9492fc4d91cfe8a362d |
| linux | linux | >= 820a6ee944e74e57255ac2e90916ecdaade57b95 < 1e2848bda819af569dfe7ab186223855e092a2cb | 1e2848bda819af569dfe7ab186223855e092a2cb |
| linux | linux | >= 820a6ee944e74e57255ac2e90916ecdaade57b95 < f577508cc8a0adb8b4ebe9480bba7683b6149930 | f577508cc8a0adb8b4ebe9480bba7683b6149930 |
| linux | linux | >= 820a6ee944e74e57255ac2e90916ecdaade57b95 < eea6f395ca502c4528314c8112da9b5d65f685eb | eea6f395ca502c4528314c8112da9b5d65f685eb |
| linux | linux | >= 820a6ee944e74e57255ac2e90916ecdaade57b95 < b45f721775947a84996deb5c661602254ce25ce6 | b45f721775947a84996deb5c661602254ce25ce6 |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | >= 0 < 6.1.162-1 | 6.1.162-1 |
| linux | linux_kernel | >= 0 < 6.12.69-1 | 6.12.69-1 |
| linux | linux_kernel | >= 0 < 6.18.8-1 | 6.18.8-1 |
| linux | linux_kernel | >= 5.17.0 < 6.1.162 | 6.1.162 |
| linux | linux_kernel | >= 5.17.1 < 6.1.162 | 6.1.162 |
| linux | linux_kernel | >= 6.13 < 6.18.7 | 6.18.7 |
| linux | linux_kernel | >= 6.13.0 < 6.18.7 | 6.18.7 |
| linux | linux_kernel | >= 6.2 < 6.6.122 | 6.6.122 |
CVSS provenance
nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.5MEDIUM
vendor_ubuntu7.8HIGH
vendor_debian5.5MEDIUM
vendor_redhat5.5MEDIUM
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- DPLL subsystem;
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Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
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- ARM64 architecture;
- x86 architecture;
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It was discovered that the Linux kernel algif_aead module did not properly
handle in-place cryptographic operations. This flaw is known as Copy Fail.
A local attacker could use this to escalate privileges, or possibly escape
a container. (CVE-2026-31431)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- ARM64 architecture;
- x86 architecture;
- Cryptographic API;
- Compute Acceleration Framework;
- Drivers core;
- Null block device driver;
- Ublk userspace block driver;
- Bluetooth drivers;
- Counter interface drivers;
- DMA engine subsystem;
- DPLL
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An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- ARM64 architecture;
- x86 architecture;
- Compute Acceleration Framework;
- Drivers core;
- Null block device driver;
- Ublk userspace block driver;
- Bluetooth drivers;
- Counter interface drivers;
- DMA engine subsystem;
- DPLL subsystem;
- GPU drivers;
- HID subsystem;
- Intel Trace Hub HW tracing drivers;
- IIO ADC drivers;
- IIO subsystem;
- On-Chip Interconnect management framework;
- IRQ chip drivers;
- Modular ISDN driver;
- LED subsystem;
- Multiple devices driver;
- UACCE accelerator framework
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Title: Linux kernel (NVIDIA) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that the Linux kernel algif_aead module did not properly
handle in-place cryptographic operations. This flaw is known as Copy Fail.
A local attacker could use this to escalate privileges, or possibly escape
a container. (CVE-2026-31431)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- ARM64 architecture;
- x86 architecture;
- Cryptographic API;
- Compute Acceleration Framework;
- Drivers core;
- Null block device driver;
- Ublk userspace block driver;
- Bluetooth drivers;
- Counter interface drivers;
- DMA engine subsystem;
- DPLL
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Summary: Several security issues were fixed in the Linux kernel.
It was discovered that the Linux kernel algif_aead module did not properly
handle in-place cryptographic operations. This flaw is known as Copy Fail.
A local attacker could use this to escalate privileges, or possibly escape
a container. (CVE-2026-31431)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- ARM64 architecture;
- x86 architecture;
- Cryptographic API;
- Compute Acceleration Framework;
- Drivers core;
- Null block device driver;
- Ublk userspace block driver;
- Bluetooth drivers;
- Counter interface drivers;
- DMA engine subsystem;
- DPLL subsyste
Red Hat
kernel: x86/fpu: Clear XSTATE_BV[i] in guest XSAVE state whenever XFD[i]=1
vendor_redhat·2026-01-25·CVSS 5.5
CVE-2026-23005 [MEDIUM] kernel: x86/fpu: Clear XSTATE_BV[i] in guest XSAVE state whenever XFD[i]=1
kernel: x86/fpu: Clear XSTATE_BV[i] in guest XSAVE state whenever XFD[i]=1
In the Linux kernel, the following vulnerability has been resolved:
x86/fpu: Clear XSTATE_BV[i] in guest XSAVE state whenever XFD[i]=1
When loading guest XSAVE state via KVM_SET_XSAVE, and when updating XFD in
response to a guest WRMSR, clear XFD-disabled features in the saved (or to
be restored) XSTATE_BV to ensure KVM doesn't attempt to load state for
features that are disabled via the guest's XFD. Because the kernel
executes XRSTOR with the guest's XFD, saving XSTATE_BV[i]=1 with XFD[i]=1
will cause XRSTOR to #NM and panic the kernel.
E.g. if fpu_update_guest_xfd() sets XFD without clearing XSTATE_BV:
------------[ cut here ]------------
WARNING: arch/x86/kernel/traps.c:1524 at exc_device_not_available+0x101/0x1
Debian
CVE-2026-23005: linux - In the Linux kernel, the following vulnerability has been resolved: x86/fpu: Cl...
vendor_debian·2026·CVSS 5.5
CVE-2026-23005 [MEDIUM] CVE-2026-23005: linux - In the Linux kernel, the following vulnerability has been resolved: x86/fpu: Cl...
In the Linux kernel, the following vulnerability has been resolved: x86/fpu: Clear XSTATE_BV[i] in guest XSAVE state whenever XFD[i]=1 When loading guest XSAVE state via KVM_SET_XSAVE, and when updating XFD in response to a guest WRMSR, clear XFD-disabled features in the saved (or to be restored) XSTATE_BV to ensure KVM doesn't attempt to load state for features that are disabled via the guest's XFD. Because the kernel executes XRSTOR with the guest's XFD, saving XSTATE_BV[i]=1 with XFD[i]=1 will cause XRSTOR to #NM and panic the kernel. E.g. if fpu_update_guest_xfd() sets XFD without clearing XSTATE_BV: ------------[ cut here ]------------ WARNING: arch/x86/kernel/traps.c:1524 at exc_device_not_available+0x101/0x110, CPU#29: amx_test/848 Modules linked in: kvm_intel kvm irqbypass CPU: 29
OSV
x86/fpu: Clear XSTATE_BV[i] in guest XSAVE state whenever XFD[i]=1
osv·2026-01-25·CVSS 5.5
CVE-2026-23005 [MEDIUM] x86/fpu: Clear XSTATE_BV[i] in guest XSAVE state whenever XFD[i]=1
x86/fpu: Clear XSTATE_BV[i] in guest XSAVE state whenever XFD[i]=1
In the Linux kernel, the following vulnerability has been resolved:
x86/fpu: Clear XSTATE_BV[i] in guest XSAVE state whenever XFD[i]=1
When loading guest XSAVE state via KVM_SET_XSAVE, and when updating XFD in
response to a guest WRMSR, clear XFD-disabled features in the saved (or to
be restored) XSTATE_BV to ensure KVM doesn't attempt to load state for
features that are disabled via the guest's XFD. Because the kernel
executes XRSTOR with the guest's XFD, saving XSTATE_BV[i]=1 with XFD[i]=1
will cause XRSTOR to #NM and panic the kernel.
E.g. if fpu_update_guest_xfd() sets XFD without clearing XSTATE_BV:
------------[ cut here ]------------
WARNING: arch/x86/kernel/traps.c:1524 at exc_device_not_available+0x101/0x110,
GHSA
GHSA-326g-5c6q-7782: In the Linux kernel, the following vulnerability has been resolved:
x86/fpu: Clear XSTATE_BV[i] in guest XSAVE state whenever XFD[i]=1
When loading
ghsa_unreviewed·2026-01-25
CVE-2026-23005 [MEDIUM] GHSA-326g-5c6q-7782: In the Linux kernel, the following vulnerability has been resolved:
x86/fpu: Clear XSTATE_BV[i] in guest XSAVE state whenever XFD[i]=1
When loading
In the Linux kernel, the following vulnerability has been resolved:
x86/fpu: Clear XSTATE_BV[i] in guest XSAVE state whenever XFD[i]=1
When loading guest XSAVE state via KVM_SET_XSAVE, and when updating XFD in
response to a guest WRMSR, clear XFD-disabled features in the saved (or to
be restored) XSTATE_BV to ensure KVM doesn't attempt to load state for
features that are disabled via the guest's XFD. Because the kernel
executes XRSTOR with the guest's XFD, saving XSTATE_BV[i]=1 with XFD[i]=1
will cause XRSTOR to #NM and panic the kernel.
E.g. if fpu_update_guest_xfd() sets XFD without clearing XSTATE_BV:
------------[ cut here ]------------
WARNING: arch/x86/kernel/traps.c:1524 at exc_device_not_available+0x101/0x110, CPU#29: amx_test/848
Modules linked in: kvm_intel kvm irqbypass
CPU:
OSV
CVE-2026-23005: In the Linux kernel, the following vulnerability has been resolved: x86/fpu: Clear XSTATE_BV[i] in guest XSAVE state whenever XFD[i]=1 When loading gu
osv·2026-01-25·CVSS 5.5
CVE-2026-23005 [MEDIUM] CVE-2026-23005: In the Linux kernel, the following vulnerability has been resolved: x86/fpu: Clear XSTATE_BV[i] in guest XSAVE state whenever XFD[i]=1 When loading gu
In the Linux kernel, the following vulnerability has been resolved: x86/fpu: Clear XSTATE_BV[i] in guest XSAVE state whenever XFD[i]=1 When loading guest XSAVE state via KVM_SET_XSAVE, and when updating XFD in response to a guest WRMSR, clear XFD-disabled features in the saved (or to be restored) XSTATE_BV to ensure KVM doesn't attempt to load state for features that are disabled via the guest's XFD. Because the kernel executes XRSTOR with the guest's XFD, saving XSTATE_BV[i]=1 with XFD[i]=1 will cause XRSTOR to #NM and panic the kernel. E.g. if fpu_update_guest_xfd() sets XFD without clearing XSTATE_BV: ------------[ cut here ]------------ WARNING: arch/x86/kernel/traps.c:1524 at exc_device_not_available+0x101/0x110, CPU#29: amx_test/848 Modules linked in: kvm_intel kvm irqbypass CPU: 29
No detection rules found.
No public exploits indexed.
https://git.kernel.org/stable/c/1e2848bda819af569dfe7ab186223855e092a2cbhttps://git.kernel.org/stable/c/b45f721775947a84996deb5c661602254ce25ce6https://git.kernel.org/stable/c/b5995c01ba53d84182ecb9492fc4d91cfe8a362dhttps://git.kernel.org/stable/c/eea6f395ca502c4528314c8112da9b5d65f685ebhttps://git.kernel.org/stable/c/f577508cc8a0adb8b4ebe9480bba7683b6149930https://cert-portal.siemens.com/productcert/html/ssa-019113.html
2026-01-25
Published