csirt@kutim:~/threat-intel/cve/CVE-2021-28689

Katalog CVE

CVSS 5.5 · Medium EPSS 0,36%

Kerentanan Improper Removal of Sensitive Information Before Storage or Transfer pada xen. Skor CVSS 3.1 5.5 (Medium) menurut NVD.

Deskripsi (NVD)

x86: Speculative vulnerabilities with bare (non-shim) 32-bit PV guests 32-bit x86 PV guest kernels run in ring 1. At the time when Xen was developed, this area of the i386 architecture was rarely used, which is why Xen was able to use it to implement paravirtualisation, Xen's novel approach to virtualization. In AMD64, Xen had to use a different implementation approach, so Xen does not use ring 1 to support 64-bit guests. With the focus now being on 64-bit systems, and the availability of explicit hardware support for virtualization, fixing speculation issues in ring 1 is not a priority for processor companies. Indirect Branch Restricted Speculation (IBRS) is an architectural x86 extension put together to combat speculative execution sidechannel attacks, including Spectre v2. It was retrofitted in microcode to existing CPUs. For more details on Spectre v2, see: http://xenbits.xen.org/xsa/advisory-254.html However, IBRS does not architecturally protect ring 0 from predictions learnt in ring 1. For more details, see: https://software.intel.com/security-software-guidance/deep-dives/deep-dive-indirect-branch-restricted-speculation Similar situations may exist with other mitigations for other kinds of speculative execution attacks. The situation is quite likely to be similar for speculative execution attacks which have yet to be discovered, disclosed, or mitigated.

Rincian

Terbit di NVD
11 Juni 2021
Terakhir diubah
17 Juni 2026
Status NVD
Modified
CVSS 3.1
5.5 (Medium), sumber NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N · uraikan di kalkulator
Jenis kelemahan (CWE)
CWE-212: Improper Removal of Sensitive Information Before Storage or Transfer
EPSS (30 hari)
0,36% peluang dieksploitasi; lebih tinggi dari 27,9% CVE lain

Produk dan versi terdampak

VendorProdukVersi terdampak
xen xen Semua versi sebelum 4.12.0

> 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.