Azure Linux 3.0 安全性更新核心 (CVE-2025-21991)
high Nessus Plugin ID 295499
語言:
概要
遠端 Azure Linux 主機缺少一個或多個安全性更新。說明
遠端 Azure Linux 3.0 主機上安裝的核心版本比測試版舊。因此，此版本會受到 CVE-2025-21991 公告中提及的一個弱點影響。- 已解決 Linux 核心中的下列弱點：x86/microcode/AMD: Fix out-of-bounds on systems with CPU-less NUMA nodes Currently, load_microcode_amd() iterates over all NUMA nodes, retrieves their CPU masks and unconditionally accesses per-CPU data for the first CPU of each mask.
According to Documentation/admin-guide/mm/numaperf.rst: Some memory May share the same node as a CPU, and others are provided as memory only nodes. Therefore, some node CPU masks May be empty and wouldn't have a first CPU. On a machine with far memory (and therefore CPU-less NUMA nodes): - cpumask_of_node(nid) is 0
- cpumask_first(0) is CONFIG_NR_CPUS - cpu_data(CONFIG_NR_CPUS) accesses the cpu_info per-CPU array at an index that is 1 out of bounds This does not have any security implications since flashing microcode is a privileged operation but I believe this has reliability implications by potentially corrupting memory while flashing a microcode update. When booting with CONFIG_UBSAN_BOUNDS=y on an AMD machine that flashes a microcode update. I get the following splat: UBSAN: array-index-out-of-bounds in arch/x86/kernel/cpu/microcode/amd.c:X:Y index 512 is out of range for type 'unsigned long[512]' [...] Call Trace: dump_stack __ubsan_handle_out_of_bounds load_microcode_amd request_microcode_amd reload_store kernfs_fop_write_iter vfs_write ksys_write do_syscall_64 entry_SYSCALL_64_after_hwframe Change the loop to go over only NUMA nodes which have CPUs before determining whether the first CPU on the respective node needs microcode update. [ bp: Massage commit message, fix typo. ] (CVE-2025-21991)
請注意，Nessus 並未測試此問題，而是僅依據應用程式自我報告的版本號碼作出判斷。
解決方案
更新受影響的套件。另請參閱
Plugin 詳細資訊
嚴重性: High
ID: 295499
檔案名稱: azure_linux_CVE-2025-21991.nasl
版本: 1.1
類型: local
已發布: 2026/1/22
已更新: 2026/1/22
支援的感應器: Nessus
風險資訊
VPR
風險因素: Medium
分數: 6.7
CVSS v2
風險因素: Medium
基本分數: 6.8
時間性分數: 5
媒介: CVSS2#AV:L/AC:L/Au:S/C:C/I:C/A:C
CVSS 評分資料來源: CVE-2025-21991
CVSS v3
風險因素: High
基本分數: 7.8
時間性分數: 6.8
媒介: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
時間媒介: CVSS:3.0/E:U/RL:O/RC:C
弱點資訊
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
必要的 KB 項目: Host/local_checks_enabled, Host/AzureLinux/release, Host/AzureLinux/rpm-list, Host/cpu
可輕鬆利用: No known exploits are available
修補程式發佈日期: 2025/5/13
弱點發布日期: 2025/4/2
參考資訊
CVE: CVE-2025-21991