CVE-2026-23553
2.9
LOW
CVSS 3.1
EPSS 0.13%
描述
In the context switch logic Xen attempts to skip an IBPB in the case of a vCPU returning to a CPU on which it was the previous vCPU to run. While safe for Xen's isolation between vCPUs, this prevents the guest kernel correctly isolating between tasks. Consider: 1) vCPU runs on CPU A, running task 1. 2) vCPU moves to CPU B, idle gets scheduled on A. Xen skips IBPB. 3) On CPU B, guest kernel switches from task 1 to 2, issuing IBPB. 4) vCPU moves back to CPU A. Xen skips IBPB again. Now, task 2 is running on CPU A with task 1's training still in the BTB.
如何修補 CVE-2026-23553
要修補 CVE-2026-23553,請將受影響套件升級到下列已修補版本。
- —升級至 4.18.5-r4 或更新版本
CVE-2026-23553 正在被利用嗎?
低 — EPSS 為 0.1%,目前沒有觀察到大規模利用活動。
受影響套件(1)
- >= 4.6.0, < 4.18.5-r4
CVSS 分數
| 來源 | 版本 | 嚴重程度 | 向量 |
|---|---|---|---|
| osv | CVSS 3.1 | LOW2.9 | CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N |