csirt@kutim:~/threat-intel/cve/CVE-2021-47226

Katalog CVE

CVSS 7.1 · High EPSS 0,22%

Kerentanan Observable Discrepancy pada linux kernel. Skor CVSS 3.1 7.1 (High) menurut NVD.

Deskripsi (NVD)

In the Linux kernel, the following vulnerability has been resolved: x86/fpu: Invalidate FPU state after a failed XRSTOR from a user buffer Both Intel and AMD consider it to be architecturally valid for XRSTOR to fail with #PF but nonetheless change the register state. The actual conditions under which this might occur are unclear [1], but it seems plausible that this might be triggered if one sibling thread unmaps a page and invalidates the shared TLB while another sibling thread is executing XRSTOR on the page in question. __fpu__restore_sig() can execute XRSTOR while the hardware registers are preserved on behalf of a different victim task (using the fpu_fpregs_owner_ctx mechanism), and, in theory, XRSTOR could fail but modify the registers. If this happens, then there is a window in which __fpu__restore_sig() could schedule out and the victim task could schedule back in without reloading its own FPU registers. This would result in part of the FPU state that __fpu__restore_sig() was attempting to load leaking into the victim task's user-visible state. Invalidate preserved FPU registers on XRSTOR failure to prevent this situation from corrupting any state. [1] Frequent readers of the errata lists might imagine "complex microarchitectural conditions".

Rincian

Terbit di NVD
21 Mei 2024
Terakhir diubah
4 Agustus 2026
Status NVD
Modified
CVSS 3.1
7.1 (High), sumber NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H · uraikan di kalkulator
Jenis kelemahan (CWE)
CWE-203: Observable Discrepancy
EPSS (30 hari)
0,22% peluang dieksploitasi; lebih tinggi dari 12,0% CVE lain

Produk dan versi terdampak

VendorProdukVersi terdampak
linux linux kernel Versi 5.2 hingga sebelum 5.10.46
linux linux kernel Versi 5.11 hingga sebelum 5.12.13
linux linux kernel Versi 5.13 rc1
linux linux kernel Versi 5.13 rc2
linux linux kernel Versi 5.13 rc3
linux linux kernel Versi 5.13 rc4
linux linux kernel Versi 5.13 rc5
linux linux kernel Versi 5.13 rc6

> Data dari konfigurasi CPE di NVD.

Referensi dan perbaikan

Sumber: NVD · CVE.org · EPSS. Halaman ini disusun otomatis dari data tersebut; pembaruan terakhir 5 Okt 2026, 20:10 WITA. Kalau sistem di Perangkat Daerah memakai produk ini dan butuh bantuan, laporkan lewat kanal pelaporan.