Azure Linux 3.0 安全更新内核 (CVE-2024-43853)

medium Nessus 插件 ID 215343

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-2024-43853 公告中提及的一个漏洞影响。

- 已修复 Linux 内核中的下列漏洞:cgroup/cpuset: Prevent UAF in proc_cpuset_show() An UAF can happen when /proc/cpuset is read as reported in [1]. This can be reproduced by the following methods: 1.add an mdelay(1000) before acquiring the cgroup_lock In the cgroup_path_ns function. 2.$cat /proc/<pid>/cpuset repeatly. 3.$mount -t cgroup -o cpuset cpuset /sys/fs/cgroup/cpuset/ $umount /sys/fs/cgroup/cpuset/ repeatly. The race that cause this bug can be shown as below: (umount) | (cat /proc/<pid>/cpuset) css_release | proc_cpuset_show css_release_work_fn | css = task_get_css(tsk, cpuset_cgrp_id); css_free_rwork_fn | cgroup_path_ns(css->cgroup, ...); cgroup_destroy_root | mutex_lock(&cgroup_mutex); rebind_subsystems | cgroup_free_root | | // cgrp was freed, UAF | cgroup_path_ns_locked(cgrp,..); When the cpuset is initialized, the root node top_cpuset.css.cgrp will point to &cgrp_dfl_root.cgrp. In cgroup v1, the mount operation will allocate cgroup_root, and top_cpuset.css.cgrp will point to the allocated &cgroup_root.cgrp. When the umount operation is executed, top_cpuset.css.cgrp will be rebound to &cgrp_dfl_root.cgrp. The problem is that when rebinding to cgrp_dfl_root, there are cases where the cgroup_root allocated by setting up the root for cgroup v1 is cached. This could lead to a Use-After-Free (UAF) if it is subsequently freed. The descendant cgroups of cgroup v1 can only be freed after the css is released. However, the css of the root will never be released, yet the cgroup_root should be freed when it is unmounted. This means that obtaining a reference to the css of the root does not guarantee that css.cgrp->root will not be freed. Fix this problem by using rcu_read_lock in proc_cpuset_show(). As cgroup_root is kfree_rcu after commit d23b5c577715 (cgroup: Make operations on the cgroup root_list RCU safe), css->cgroup won't be freed during the critical section. To call cgroup_path_ns_locked, css_set_lock is needed, so it is safe to replace task_get_css with task_css.
[1] https://syzkaller.appspot.com/bug?extid=9b1ff7be974a403aa4cd (CVE-2024-43853)

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-2024-43853

插件详情

严重性: Medium

ID: 215343

文件名: azure_linux_CVE-2024-43853.nasl

版本: 1.1

类型: local

发布时间: 2025/2/10

最近更新时间: 2025/2/10

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-2024-43853

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:kernel-dtb, 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-accessibility, p-cpe:/a:microsoft:azure_linux:kernel-tools

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

易利用性: No known exploits are available

补丁发布日期: 2024/10/8

漏洞发布日期: 2024/8/17

参考资料信息

CVE: CVE-2024-43853