Azure Linux 3.0 安全更新内核 (CVE-2025-37936)

medium Nessus 插件 ID 295485

简介

远程 Azure Linux 主机缺少一个或多个安全更新。

描述

远程 Azure Linux 3.0 主机上安装的内核版本低于 测试的版本。因此,该程序受到 CVE-2025-37936 公告中提及的一个漏洞影响。

- 已修复 Linux 内核中的下列漏洞:perf/x86/intel: KVM: Mask PEBS_ENABLE loaded for guest with vCPU's value. When generating the MSR_IA32_PEBS_ENABLE value that will be loaded on VM-Entry to a KVM guest, mask the value with the vCPU's desired PEBS_ENABLE value. Consulting only the host kernel's host vs. guest masks results in running the guest with PEBS enabled even when the guest doesn't want to use PEBS. Because KVM uses perf events to proxy the guest virtual PMU, simply looking at exclude_host can't differentiate between events created by host userspace, and events created by KVM on behalf of the guest. Running the guest with PEBS unexpectedly enabled typically manifests as crashes due to a near-infinite stream of #PFs. E.g. if the guest hasn't written MSR_IA32_DS_AREA, the CPU will hit page faults on address '0' when trying to record PEBS events. The issue is most easily reproduced by running `perf kvm top` from before commit 7b100989b4f6 (perf evlist: Remove __evlist__add_default) (after which, `perf kvm top` effectively stopped using PEBS). The userspace side of perf creates a guest-only PEBS event, which intel_guest_get_msrs() misconstrues a guest-*owned* PEBS event. Arguably, this is a userspace bug, as enabling PEBS on guest-only events simply cannot work, and userspace can kill VMs in many other ways (there is no danger to the host). However, even if this is considered to be bad userspace behavior, there's zero downside to perf/KVM restricting PEBS to guest-owned events. Note, commit 854250329c02 (KVM: x86/pmu: Disable guest PEBS temporarily in two rare situations) fixed the case where host userspace is profiling KVM *and* userspace, but missed the case where userspace is profiling only KVM. (CVE-2025-37936)

请注意,Nessus 尚未测试此问题,而是只依据应用程序自我报告的版本号进行判断。

解决方案

更新受影响的程序包。

另见

https://nvd.nist.gov/vuln/detail/CVE-2025-37936

插件详情

严重性: Medium

ID: 295485

文件名: azure_linux_CVE-2025-37936.nasl

版本: 1.1

类型: local

发布时间: 2026/1/22

最近更新时间: 2026/1/22

支持的传感器: Nessus

风险信息

VPR

风险因素: Medium

分数: 4.4

CVSS v2

风险因素: Medium

基本分数: 4.6

时间分数: 3.4

矢量: CVSS2#AV:L/AC:L/Au:S/C:N/I:N/A:C

CVSS 分数来源: CVE-2025-37936

CVSS v3

风险因素: Medium

基本分数: 5.5

时间分数: 4.8

矢量: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

时间矢量: CVSS:3.0/E:U/RL:O/RC:C

漏洞信息

CPE: p-cpe:/a:microsoft:azure_linux:kernel-debuginfo, p-cpe:/a:microsoft:azure_linux:kernel-devel, p-cpe:/a:microsoft:azure_linux:kernel-drivers-gpu, p-cpe:/a:microsoft:azure_linux:python3-perf, p-cpe:/a:microsoft:azure_linux:kernel-docs, x-cpe:/o:microsoft:azure_linux, p-cpe:/a:microsoft:azure_linux:kernel, p-cpe:/a:microsoft:azure_linux:kernel-drivers-sound, p-cpe:/a:microsoft:azure_linux:bpftool, p-cpe:/a:microsoft:azure_linux:kernel-drivers-intree-amdgpu, p-cpe:/a:microsoft:azure_linux:kernel-drivers-accessibility, p-cpe:/a:microsoft:azure_linux:kernel-tools

必需的 KB 项: Host/local_checks_enabled, Host/AzureLinux/release, Host/AzureLinux/rpm-list, Host/cpu

易利用性: No known exploits are available

补丁发布日期: 2025/7/8

漏洞发布日期: 2025/5/13

参考资料信息

CVE: CVE-2025-37936