Linux/Unix 主机中安装的一个或多个程序包受到一个漏洞影响，而供应商没有提供补丁程序。

  - 在 Linux 内核中，已解决以下漏洞： blk-cgroup: fix UAF by grabbing blkcg lock before destroying blkg pd KASAN reports a use-after-free report when doing fuzz test: [693354.104835] ================================================================== [693354.105094] BUG: KASAN: use-after-free in bfq_io_set_weight_legacy+0xd3/0x160 [693354.105336] Read of size 4 at addr ffff888be0a35664 by task sh/1453338 [693354.105607] CPU: 41 PID: 1453338 Comm: sh Kdump: loaded Not tainted 4.18.0-147 [693354.105610] Hardware name: Huawei 2288H V5/BC11SPSCB0, BIOS 0.81 07/02/2018 [693354.105612] Call Trace: [693354.105621] dump_stack+0xf1/0x19b [693354.105626] ? show_regs_print_info+0x5/0x5 [693354.105634] ? printk+0x9c/0xc3 [693354.105638] ? cpumask_weight+0x1f/0x1f [693354.105648] print_address_description+0x70/0x360 [693354.105654] kasan_report+0x1b2/0x330 [693354.105659] ? bfq_io_set_weight_legacy+0xd3/0x160 [693354.105665] ? bfq_io_set_weight_legacy+0xd3/0x160 [693354.105670] bfq_io_set_weight_legacy+0xd3/0x160 [693354.105675] ? bfq_cpd_init+0x20/0x20 [693354.105683] cgroup_file_write+0x3aa/0x510 [693354.105693] ? ___slab_alloc+0x507/0x540 [693354.105698] ? cgroup_file_poll+0x60/0x60 [693354.105702] ? 0xffffffff89600000 [693354.105708] ? usercopy_abort+0x90/0x90 [693354.105716] ? mutex_lock+0xef/0x180 [693354.105726] kernfs_fop_write+0x1ab/0x280 [693354.105732] ? cgroup_file_poll+0x60/0x60 [693354.105738] vfs_write+0xe7/0x230 [693354.105744] ksys_write+0xb0/0x140 [693354.105749] ? __ia32_sys_read+0x50/0x50 [693354.105760] do_syscall_64+0x112/0x370 [693354.105766] ? syscall_return_slowpath+0x260/0x260 [693354.105772] ? do_page_fault+0x9b/0x270 [693354.105779] ? prepare_exit_to_usermode+0xf9/0x1a0 [693354.105784] ? enter_from_user_mode+0x30/0x30 [693354.105793] entry_SYSCALL_64_after_hwframe+0x65/0xca [693354.105875] Allocated by task 1453337: [693354.106001] kasan_kmalloc+0xa0/0xd0 [693354.106006] kmem_cache_alloc_node_trace+0x108/0x220 [693354.106010] bfq_pd_alloc+0x96/0x120 [693354.106015] blkcg_activate_policy+0x1b7/0x2b0 [693354.106020] bfq_create_group_hierarchy+0x1e/0x80 [693354.106026] bfq_init_queue+0x678/0x8c0 [693354.106031] blk_mq_init_sched+0x1f8/0x460 [693354.106037] elevator_switch_mq+0xe1/0x240 [693354.106041] elevator_switch+0x25/0x40 [693354.106045] elv_iosched_store+0x1a1/0x230 [693354.106049] queue_attr_store+0x78/0xb0 [693354.106053] kernfs_fop_write+0x1ab/0x280 [693354.106056] vfs_write+0xe7/0x230 [693354.106060] ksys_write+0xb0/0x140 [693354.106064] do_syscall_64+0x112/0x370 [693354.106069] entry_SYSCALL_64_after_hwframe+0x65/0xca [693354.106114] Freed by task 1453336:
    [693354.106225] __kasan_slab_free+0x130/0x180 [693354.106229] kfree+0x90/0x1b0 [693354.106233] blkcg_deactivate_policy+0x12c/0x220 [693354.106238] bfq_exit_queue+0xf5/0x110 [693354.106241] blk_mq_exit_sched+0x104/0x130 [693354.106245] __elevator_exit+0x45/0x60 [693354.106249] elevator_switch_mq+0xd6/0x240 [693354.106253] elevator_switch+0x25/0x40 [693354.106257] elv_iosched_store+0x1a1/0x230 [693354.106261] queue_attr_store+0x78/0xb0 [693354.106264] kernfs_fop_write+0x1ab/0x280 [693354.106268] vfs_write+0xe7/0x230 [693354.106271] ksys_write+0xb0/0x140 [693354.106275] do_syscall_64+0x112/0x370 [693354.106280] entry_SYSCALL_64_after_hwframe+0x65/0xca [693354.106329] The buggy address belongs to the object at ffff888be0a35580 which belongs to the cache kmalloc-1k of size 1024 [693354.106736] The buggy address is located 228 bytes inside of 1024-byte region [ffff888be0a35580, ffff888be0a35980) [693354.107114] The buggy address belongs to the page:
    [693354.107273] page:ffffea002f828c00 count:1 mapcount:0 mapping:ffff888107c17080 index:0x0 compound_mapcount: 0 [693354.107606] flags: 0x17ffffc0008100(slab|head) [693354.107760] raw:
    0017ffffc0008100 ffffea002fcbc808 ffffea0030bd3a08 ffff888107c17080 [693354.108020] r ---truncated--- (CVE-2021-47379)

请注意，Nessus 依赖供应商报告的程序包是否存在进行判断。

远程主机上安装的内核版本低于 5.10.75-79.358。因此，会受到 ALAS2KERNEL-5.10-2022-007 公告中提及的多个漏洞影响。

    在用户使用 OverlayFS 以特定方式重命名的方式中，发现访问 Linux 内核 OverlayFS 子系统中的文件对象时存在争用条件。本地用户可利用此缺陷导致系统崩溃。
    (CVE-2021-20321)

    此漏洞允许本地攻击者提升对 Linux 内核 5.14-rc3 的受影响装置的特权。要利用此漏洞，攻击者必须首先具备在目标系统上执行低权限代码的能力。处理 eBPF 程序时存在特定缺陷。造成此问题的原因是缺少对用户提供的 eBPF 程序的正确验证，这可导致类型混淆情形。攻击者可利用此漏洞，在内核的上下文中提升特权和执行任意代码。此漏洞之前为 ZDI-CAN-14689。(CVE-2021-34866)

    在 Linux 内核中发现一个缺陷。ccp-ops crypto 驱动程序中的内存泄漏可允许攻击者造成拒绝服务。此缺陷与较早版本的 CVE-2019-18808 类似此漏洞最大的威胁在于系统可用性。(CVE-2021-3744)

    在 Linux 内核的 ccp_run_aes_gcm_cmd() 函数中发现内存泄漏缺陷，攻击者可利用此缺陷造成拒绝服务。此漏洞与早先的 CVE-2019-18808 类似。此漏洞最大的威胁在于系统可用性。(CVE-2021-3764)

    在 Linux 内核的 bpf 的 kernel/bpf/stackmap.c 的 prealloc_elems_and_freelist 中发现越界 (OOB) 内存写入缺陷。此缺陷用于计算大小的乘法运算可导致整数溢出，具有特殊用户权限的本地攻击者可获得对越界内存的访问权限，从而导致系统崩溃或内部内核泄漏信息。(CVE-2021-41864)

    在 Linux 内核的透明进程间通信实现的加密接收代码中发现一个缺陷。能够向目标发送 TIPC 消息的攻击者可损坏目标系统上的内存并升级权限。(CVE-2021-43267)

    在 Linux 内核中，以下漏洞已修复：

    binder：确保 fd closes 完整 (CVE-2021-47360)

    在 Linux 内核中，以下漏洞已修复：

    irqchip/gic-v3-its：修复因错误引起的潜在 VPE 泄漏 (CVE-2021-47373)

    在 Linux 内核中，以下漏洞已修复：

    blktrace：修复被 sysfs 删除之后 blk_trace 访问中的释放后使用问题 (CVE-2021-47375)

    在 Linux 内核中，以下漏洞已修复：

    bpf：添加调用 kvcalloc() 前的超大检查 (CVE-2021-47376)

    在 Linux 内核中，以下漏洞已修复：

    nvme-rdma：在破坏 qp 之前破坏 cm id 以避免释放后使用 (CVE-2021-47378)

    在 Linux 内核中，以下漏洞已修复：

    blk-cgroup：通过在破坏 blkg pd 之前获取 blkcg 锁定来修复 UAF (CVE-2021-47379)

    在 Linux 内核中，以下漏洞已修复：

    tty：修复 imageblit 中的 vmalloc 访问越界问题  (CVE-2021-47383)

    在 Linux 内核中，以下漏洞已修复：

    hwmon：(w83793) 通过移除不必要的结构字段来修复空指针取消引用 (CVE-2021-47384)

    在 Linux 内核中，以下漏洞已修复：

    hwmon(w83792d) 通过删除不必要的结构字段修复空指针取消引用 (CVE-2021-47385)

    在 Linux 内核中，以下漏洞已修复：

    hwmon：(w83791d) 通过移除不必要的结构字段来修复空指针取消引用 (CVE-2021-47386)

    在 Linux 内核中，以下漏洞已修复：

    cpufreq：schedutil：使用 kobject release() 方法释放 sugov_tunables (CVE-2021-47387)

    在 Linux 内核中，以下漏洞已修复：

    KVM: x86：修复从 ioapic_write_indirect() 进行的堆栈越界内存访问 (CVE-2021-47390)

    在 Linux 内核中，以下漏洞已修复：

    RDMA/cma修复 rdma_cma_listen_on_all() 失败中的侦听器泄漏 (CVE-2021-47392)

    在 Linux 内核中，以下漏洞已修复：

    sctp如果 skb_header_pointer 在 sctp_rcv_ootb 中返回 NULL 则中断 (CVE-2021-47397)

    在 Linux 内核中，以下漏洞已修复：

    ixgbe修复 ixgbe_xdp_setup 中的空指针取消引用 (CVE-2021-47399)

    在 Linux 内核中，以下漏洞已修复：

    HID：betop：修复 betop_probe 中的 slab-out-of-bound 写入 (CVE-2021-47404)

    在 Linux 内核中，以下漏洞已修复：

    HIDusbhid释放 usbhid_stop 中的 raw_report 缓冲区 (CVE-2021-47405)

    在 Linux 内核中，以下漏洞已修复：

    ext4：向 ext4_ext_replay_set_iblocks() 添加错误检查 (CVE-2021-47406)

    在 Linux 内核中，以下漏洞已修复：

    KVM：x86：处理页面跟踪初始化期间的 SRCU 初始化失败 (CVE-2021-47407)

    在 Linux 内核中，以下漏洞已修复：

    netfilter：conntrack：序列化哈希调整大小和清理 (CVE-2021-47408)

    在 Linux 内核中，以下漏洞已修复：

    phymdio修复内存泄漏 (CVE-2021-47416)

    在 Linux 内核中，以下漏洞已修复：

    net_sched修复 fifo_set_limit() 中的空取消引用 (CVE-2021-47418)

    在 Linux 内核中，以下漏洞已修复：

    i40e修复未初始化的 misc IRQ 向量释放 (CVE-2021-47424)

    在 Linux 内核中，以下漏洞已修复：

    i2cacpi修复重新配置设备添加中的资源泄漏 (CVE-2021-47425)

    在 Linux 内核中，以下漏洞已修复：

    x86/entry当 CONFIG_X86_SMAP=n 时清除 X86_FEATURE_SMAP (CVE-2021-47430)

    在 Linux 内核中，以下漏洞已修复：

    btrfs修复 btrfs_replace_file_extents 中的中止逻辑 (CVE-2021-47433)

    在 Linux 内核中，以下漏洞已修复：

    xhci修复了中止命令时的命令环指针损坏 (CVE-2021-47434)

    在 Linux 内核中，以下漏洞已修复：

    net/mlx5e修复了 mlx5_core_destroy_cq() 错误路径中的内存泄漏 (CVE-2021-47438)

    在 Linux 内核中，以下漏洞已修复：

    drm/edid在 connector_bad_edid() 中按 num_blocks 读取上限 num_of_ext (CVE-2021-47444)

    在 Linux 内核中，以下漏洞已修复：

    nvmem：修复字节大小单元格的位移越界 (UBSAN) 问题 (CVE-2021-47497)

Tenable 已直接从测试产品的安全公告中提取上述描述块。

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

CentOS Linux 8.5 主机上存在安装的程序包，该程序包受到 TuxCare CENTOS8.5：CLSA-2026：1783414155公告中提及的多个漏洞的影响。

  - 已修复 Linux 内核中的下列漏洞：blk-cgroup: fix UAF by grabbing blkcg lock before destroying blkg pd KASAN reports a use-after-free report when doing fuzz test: [693354.104835] ================================================================== [693354.105094] BUG: KASAN: use-after-free in bfq_io_set_weight_legacy+0xd3/0x160 [693354.105336] Read of size 4 at addr ffff888be0a35664 by task sh/1453338 [693354.105607] CPU: 41 PID: 1453338 Comm: sh Kdump: loaded Not tainted 4.18.0-147 [693354.105610] Hardware name: Huawei 2288H V5/BC11SPSCB0, BIOS 0.81 07/02/2018 [693354.105612] Call Trace: [693354.105621] dump_stack+0xf1/0x19b [693354.105626] ? show_regs_print_info+0x5/0x5 [693354.105634] ? printk+0x9c/0xc3 [693354.105638] ? cpumask_weight+0x1f/0x1f [693354.105648] print_address_description+0x70/0x360 [693354.105654] kasan_report+0x1b2/0x330 [693354.105659] ? bfq_io_set_weight_legacy+0xd3/0x160 [693354.105665] ? bfq_io_set_weight_legacy+0xd3/0x160 [693354.105670] bfq_io_set_weight_legacy+0xd3/0x160 [693354.105675] ? bfq_cpd_init+0x20/0x20 [693354.105683] cgroup_file_write+0x3aa/0x510 [693354.105693] ? ___slab_alloc+0x507/0x540 [693354.105698] ? cgroup_file_poll+0x60/0x60 [693354.105702] ? 0xffffffff89600000 [693354.105708] ? usercopy_abort+0x90/0x90 [693354.105716] ? mutex_lock+0xef/0x180 [693354.105726] kernfs_fop_write+0x1ab/0x280 [693354.105732] ? cgroup_file_poll+0x60/0x60 [693354.105738] vfs_write+0xe7/0x230 [693354.105744] ksys_write+0xb0/0x140 [693354.105749] ? __ia32_sys_read+0x50/0x50 [693354.105760] do_syscall_64+0x112/0x370 [693354.105766] ? syscall_return_slowpath+0x260/0x260 [693354.105772] ? do_page_fault+0x9b/0x270 [693354.105779] ? prepare_exit_to_usermode+0xf9/0x1a0 [693354.105784] ? enter_from_user_mode+0x30/0x30 [693354.105793] entry_SYSCALL_64_after_hwframe+0x65/0xca [693354.105875] Allocated by task 1453337: [693354.106001] kasan_kmalloc+0xa0/0xd0 [693354.106006] kmem_cache_alloc_node_trace+0x108/0x220 [693354.106010] bfq_pd_alloc+0x96/0x120 [693354.106015] blkcg_activate_policy+0x1b7/0x2b0 [693354.106020] bfq_create_group_hierarchy+0x1e/0x80 [693354.106026] bfq_init_queue+0x678/0x8c0 [693354.106031] blk_mq_init_sched+0x1f8/0x460 [693354.106037] elevator_switch_mq+0xe1/0x240 [693354.106041] elevator_switch+0x25/0x40 [693354.106045] elv_iosched_store+0x1a1/0x230 [693354.106049] queue_attr_store+0x78/0xb0 [693354.106053] kernfs_fop_write+0x1ab/0x280 [693354.106056] vfs_write+0xe7/0x230 [693354.106060] ksys_write+0xb0/0x140 [693354.106064] do_syscall_64+0x112/0x370 [693354.106069] entry_SYSCALL_64_after_hwframe+0x65/0xca [693354.106114] Freed by task 1453336:
    [693354.106225] __kasan_slab_free+0x130/0x180 [693354.106229] kfree+0x90/0x1b0 [693354.106233] blkcg_deactivate_policy+0x12c/0x220 [693354.106238] bfq_exit_queue+0xf5/0x110 [693354.106241] blk_mq_exit_sched+0x104/0x130 [693354.106245] __elevator_exit+0x45/0x60 [693354.106249] elevator_switch_mq+0xd6/0x240 [693354.106253] elevator_switch+0x25/0x40 [693354.106257] elv_iosched_store+0x1a1/0x230 [693354.106261] queue_attr_store+0x78/0xb0 [693354.106264] kernfs_fop_write+0x1ab/0x280 [693354.106268] vfs_write+0xe7/0x230 [693354.106271] ksys_write+0xb0/0x140 [693354.106275] do_syscall_64+0x112/0x370 [693354.106280] entry_SYSCALL_64_after_hwframe+0x65/0xca [693354.106329] The buggy address belongs to the object at ffff888be0a35580 which belongs to the cache kmalloc-1k of size 1024 [693354.106736] The buggy address is located 228 bytes inside of 1024-byte region [ffff888be0a35580, ffff888be0a35980) [693354.107114] The buggy address belongs to the page:
    [693354.107273] page:ffffea002f828c00 count:1 mapcount:0 mapping:ffff888107c17080 index:0x0 compound_mapcount: 0 [693354.107606] flags: 0x17ffffc0008100(slab|head) [693354.107760] raw:
    0017ffffc0008100 ffffea002fcbc808 ffffea0030bd3a08 ffff888107c17080 [693354.108020] r ---truncated--- (CVE-2021-47379)

  - 在 Linux 内核的 Netfilter 子系统中发现一个缺陷。nfnl_osf_add_callback 函数未验证用户模式控制的 opt_num 字段。本地特权 (CAP_NET_ADMIN) 攻击者可利用此缺陷触发越界读取，从而导致程序崩溃或信息泄露。(CVE-2023-39189)

  - 已修复 Linux 内核中的下列漏洞：can: bcm: add locking for bcm_op runtime updates The CAN broadcast manager (CAN BCM) can send a sequence of CAN frames via hrtimer. The content and also the length of the sequence can be changed resp reduced at runtime where the 'currframe' counter is then set to zero. Although this appeared to be a safe operation the updates of 'currframe' can be triggered from user space and hrtimer context in bcm_can_tx(). Anderson Nascimento created a proof of concept that triggered a KASAN slab-out-of-bounds read access which can be prevented with a spin_lock_bh.
    At the rework of bcm_can_tx() the 'count' variable has been moved into the protected section as this variable can be modified from both contexts too. (CVE-2025-38004)

  - 已修复 Linux 内核中的下列漏洞：smb3: fix for slab out of bounds on mount to ksmbd With KASAN enabled, it is possible to get a slab out of bounds during mount to ksmbd due to missing check in parse_server_interfaces() (see below): BUG: KASAN: slab-out-of-bounds in parse_server_interfaces+0x14ee/0x1880 [cifs] Read of size 4 at addr ffff8881433dba98 by task mount/9827 CPU: 5 UID: 0 PID: 9827 Comm: mount Tainted: G OE 6.16.0-rc2-kasan #2 PREEMPT(voluntary) Tainted:
    [O]=OOT_MODULE, [E]=UNSIGNED_MODULE Hardware name: Dell Inc. Precision Tower 3620/0MWYPT, BIOS 2.13.1 06/14/2019 Call Trace: <TASK> dump_stack_lvl+0x9f/0xf0 print_report+0xd1/0x670
    __virt_addr_valid+0x22c/0x430 ? parse_server_interfaces+0x14ee/0x1880 [cifs] ? kasan_complete_mode_report_info+0x2a/0x1f0 ? parse_server_interfaces+0x14ee/0x1880 [cifs] kasan_report+0xd6/0x110 parse_server_interfaces+0x14ee/0x1880 [cifs]
    __asan_report_load_n_noabort+0x13/0x20 parse_server_interfaces+0x14ee/0x1880 [cifs] ?
    __pfx_parse_server_interfaces+0x10/0x10 [cifs] ? trace_hardirqs_on+0x51/0x60 SMB3_request_interfaces+0x1ad/0x3f0 [cifs] ? __pfx_SMB3_request_interfaces+0x10/0x10 [cifs] ? SMB2_tcon+0x23c/0x15d0 [cifs] smb3_qfs_tcon+0x173/0x2b0 [cifs] ? __pfx_smb3_qfs_tcon+0x10/0x10 [cifs] ? cifs_get_tcon+0x105d/0x2120 [cifs] ? do_raw_spin_unlock+0x5d/0x200 ? cifs_get_tcon+0x105d/0x2120 [cifs] ?
    __pfx_smb3_qfs_tcon+0x10/0x10 [cifs] cifs_mount_get_tcon+0x369/0xb90 [cifs] ? dfs_cache_find+0xe7/0x150 [cifs] dfs_mount_share+0x985/0x2970 [cifs] ? check_path.constprop.0+0x28/0x50 ? save_trace+0x54/0x370 ?
    __pfx_dfs_mount_share+0x10/0x10 [cifs] ? __lock_acquire+0xb82/0x2ba0 ? __kasan_check_write+0x18/0x20 cifs_mount+0xbc/0x9e0 [cifs] ? __pfx_cifs_mount+0x10/0x10 [cifs] ? do_raw_spin_unlock+0x5d/0x200 ? cifs_setup_cifs_sb+0x29d/0x810 [cifs] cifs_smb3_do_mount+0x263/0x1990 [cifs] (CVE-2025-38728)

  - 已修复 Linux 内核中的下列漏洞：iommu: disable SVA when CONFIG_X86 is set Patch series Fix stale IOTLB entries for kernel address space, v7. This proposes a fix for a security vulnerability related to IOMMU Shared Virtual Addressing (SVA). In an SVA context, an IOMMU can cache kernel page table entries. When a kernel page table page is freed and reallocated for another purpose, the IOMMU might still hold stale, incorrect entries. This can be exploited to cause a use-after-free or write-after-free condition, potentially leading to privilege escalation or data corruption. This solution introduces a deferred freeing mechanism for kernel page table pages, which provides a safe window to notify the IOMMU to invalidate its caches before the page is reused. This patch (of 8): In the IOMMU Shared Virtual Addressing (SVA) context, the IOMMU hardware shares and walks the CPU's page tables. The x86 architecture maps the kernel's virtual address space into the upper portion of every process's page table. Consequently, in an SVA context, the IOMMU hardware can walk and cache kernel page table entries.
    The Linux kernel currently lacks a notification mechanism for kernel page table changes, specifically when page table pages are freed and reused. The IOMMU driver is only notified of changes to user virtual address mappings. This can cause the IOMMU's internal caches to retain stale entries for kernel VA. Use-After-Free (UAF) and Write-After-Free (WAF) conditions arise when kernel page table pages are freed and later reallocated. The IOMMU could misinterpret the new data as valid page table entries. The IOMMU might then walk into attacker-controlled memory, leading to arbitrary physical memory DMA access or privilege escalation. This is also a Write-After-Free issue, as the IOMMU will potentially continue to write Accessed and Dirty bits to the freed memory while attempting to walk the stale page tables. Currently, SVA contexts are unprivileged and cannot access kernel mappings. However, the IOMMU will still walk kernel-only page tables all the way down to the leaf entries, where it realizes the mapping is for the kernel and errors out. This means the IOMMU still caches these intermediate page table entries, making the described vulnerability a real concern. Disable SVA on x86 architecture until the IOMMU can receive notification to flush the paging cache before freeing the CPU kernel page table pages. (CVE-2025-71089)

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

远程 Ubuntu 14.04 LTS / 16.04 LTS / 18.04 LTS 主机上安装的一个程序包受到 USN-7627-1 公告中提及的多个漏洞的影响。

    在 Linux 内核中发现多个安全问题。攻击者可能利用这些问题入侵系统。此更新修正了以下子系统中的缺陷：

    - PowerPC 架构；

    - 区块层子系统；

    - ACPI 驱动程序；

    - NILFS2 文件系统；

    - 文件系统基础设施；

    - 内存管理；

    - 网络流量控制；

    - USB 音频设备；（CVE-2025-37932、CVE-2024-53197、CVE-2024-50116、CVE-2021-47379、CVE-2024-49958、CVE-2022-49179、CVE-2024-46787、CVE-2024-41070、CVE-2025-38000、CVE-2024-56662、CVE-2022-49176、CVE-2025-37798）

Tenable 已直接从 Ubuntu 安全公告中提取上述描述块。

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

CentOS Linux 8.4 主机上存在安装的程序包，该程序包受到 TuxCare CENTOS8.4：CLSA-2026：U 1783414634公告中提及的多个漏洞的影响。

  - 已修复 Linux 内核中的下列漏洞：KVM: x86/mmu: Don't advance iterator after restart due to yielding After dropping mmu_lock in the TDP MMU, restart the iterator during tdp_iter_next() and do not advance the iterator. Advancing the iterator results in skipping the top-level SPTE and all its children, which is fatal if any of the skipped SPTEs were not visited before yielding.
    When zapping all SPTEs, i.e. when min_level == root_level, restarting the iter and then invoking tdp_iter_next() is always fatal if the current gfn has as a valid SPTE, as advancing the iterator results in try_step_side() skipping the current gfn, which wasn't visited before yielding. Sprinkle WARNs on iter->yielded being true in various helpers that are often used in conjunction with yielding, and tag the helper with __must_check to reduce the probabily of improper usage. Failing to zap a top-level SPTE manifests in one of two ways. If a valid SPTE is skipped by both kvm_tdp_mmu_zap_all() and kvm_tdp_mmu_put_root(), the shadow page will be leaked and KVM will WARN accordingly. WARNING: CPU: 1 PID:
    3509 at arch/x86/kvm/mmu/tdp_mmu.c:46 [kvm] RIP: 0010:kvm_mmu_uninit_tdp_mmu+0x3e/0x50 [kvm] Call Trace:
    <TASK> kvm_arch_destroy_vm+0x130/0x1b0 [kvm] kvm_destroy_vm+0x162/0x2a0 [kvm] kvm_vcpu_release+0x34/0x60 [kvm] __fput+0x82/0x240 task_work_run+0x5c/0x90 do_exit+0x364/0xa10 ? futex_unqueue+0x38/0x60 do_group_exit+0x33/0xa0 get_signal+0x155/0x850 arch_do_signal_or_restart+0xed/0x750 exit_to_user_mode_prepare+0xc5/0x120 syscall_exit_to_user_mode+0x1d/0x40 do_syscall_64+0x48/0xc0 entry_SYSCALL_64_after_hwframe+0x44/0xae If kvm_tdp_mmu_zap_all() skips a gfn/SPTE but that SPTE is then zapped by kvm_tdp_mmu_put_root(), KVM triggers a use-after-free in the form of marking a struct page as dirty/accessed after it has been put back on the free list. This directly triggers a WARN due to encountering a page with page_count() == 0, but it can also lead to data corruption and additional errors in the kernel. WARNING: CPU: 7 PID: 1995658 at arch/x86/kvm/../../../virt/kvm/kvm_main.c:171 RIP:
    0010:kvm_is_zone_device_pfn.part.0+0x9e/0xd0 [kvm] Call Trace: <TASK> kvm_set_pfn_dirty+0x120/0x1d0 [kvm]
    __handle_changed_spte+0x92e/0xca0 [kvm] __handle_changed_spte+0x63c/0xca0 [kvm]
    __handle_changed_spte+0x63c/0xca0 [kvm] __handle_changed_spte+0x63c/0xca0 [kvm] zap_gfn_range+0x549/0x620 [kvm] kvm_tdp_mmu_put_root+0x1b6/0x270 [kvm] mmu_free_root_page+0x219/0x2c0 [kvm] kvm_mmu_free_roots+0x1b4/0x4e0 [kvm] kvm_mmu_unload+0x1c/0xa0 [kvm] kvm_arch_destroy_vm+0x1f2/0x5c0 [kvm] kvm_put_kvm+0x3b1/0x8b0 [kvm] kvm_vcpu_release+0x4e/0x70 [kvm] __fput+0x1f7/0x8c0 task_work_run+0xf8/0x1a0 do_exit+0x97b/0x2230 do_group_exit+0xda/0x2a0 get_signal+0x3be/0x1e50 arch_do_signal_or_restart+0x244/0x17f0 exit_to_user_mode_prepare+0xcb/0x120 syscall_exit_to_user_mode+0x1d/0x40 do_syscall_64+0x4d/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae Note, the underlying bug existed even before commit 1af4a96025b3 (KVM: x86/mmu: Yield in TDU MMU iter even if no SPTES changed) moved calls to tdp_mmu_iter_cond_resched() to the beginning of loops, as KVM could still incorrectly advance past a top-level entry when yielding on a lower-level entry. But with respect to leaking shadow pages, the bug was introduced by yielding before processing the current gfn. Alternatively, tdp_mmu_iter_cond_resched() could simply fall through, or callers could jump to their retry label. The downside of that approach is that tdp_mmu_iter_cond_resched() _must_ be called before anything else in the loop, and there's no easy way to enfornce that requirement. Ideally, KVM would handling the cond_resched() fully within the iterator macro (the code is actually quite clean) and avoid this entire class of bugs, but that is extremely difficult do wh ---truncated--- (CVE-2021-47094)

  - 已修复 Linux 内核中的下列漏洞：net: bridge: fix vlan tunnel dst refcnt when egressing The egress tunnel code uses dst_clone() and directly sets the result which is wrong because the entry might have 0 refcnt or be already deleted, causing number of problems. It also triggers the WARN_ON() in dst_hold()[1] when a refcnt couldn't be taken. Fix it by using dst_hold_safe() and checking if a reference was actually taken before setting the dst. [1] dmesg WARN_ON log and following refcnt errors WARNING: CPU: 5 PID: 38 at include/net/dst.h:230 br_handle_egress_vlan_tunnel+0x10b/0x134 [bridge] Modules linked in: 8021q garp mrp bridge stp llc bonding ipv6 virtio_net CPU: 5 PID: 38 Comm:
    ksoftirqd/5 Kdump: loaded Tainted: G W 5.13.0-rc3+ #360 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-1.fc33 04/01/2014 RIP: 0010:br_handle_egress_vlan_tunnel+0x10b/0x134 [bridge] Code: e8 85 bc 01 e1 45 84 f6 74 90 45 31 f6 85 db 48 c7 c7 a0 02 19 a0 41 0f 94 c6 31 c9 31 d2 44 89 f6 e8 64 bc 01 e1 85 db 75 02 <0f> 0b 31 c9 31 d2 44 89 f6 48 c7 c7 70 02 19 a0 e8 4b bc 01 e1 49 RSP:
    0018:ffff8881003d39e8 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffffa01902a0 RBP: ffff8881040c6700 R08:
    0000000000000000 R09: 0000000000000001 R10: 2ce93d0054fe0d00 R11: 54fe0d00000e0000 R12: ffff888109515000 R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000401 FS: 0000000000000000(0000) GS:ffff88822bf40000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2:
    00007f42ba70f030 CR3: 0000000109926000 CR4: 00000000000006e0 Call Trace: br_handle_vlan+0xbc/0xca [bridge]
    __br_forward+0x23/0x164 [bridge] deliver_clone+0x41/0x48 [bridge] br_handle_frame_finish+0x36f/0x3aa [bridge] ? skb_dst+0x2e/0x38 [bridge] ? br_handle_ingress_vlan_tunnel+0x3e/0x1c8 [bridge] ? br_handle_frame_finish+0x3aa/0x3aa [bridge] br_handle_frame+0x2c3/0x377 [bridge] ? __skb_pull+0x33/0x51 ? vlan_do_receive+0x4f/0x36a ? br_handle_frame_finish+0x3aa/0x3aa [bridge]
    __netif_receive_skb_core+0x539/0x7c6 ? __list_del_entry_valid+0x16e/0x1c2
    __netif_receive_skb_list_core+0x6d/0xd6 netif_receive_skb_list_internal+0x1d9/0x1fa gro_normal_list+0x22/0x3e dev_gro_receive+0x55b/0x600 ? detach_buf_split+0x58/0x140 napi_gro_receive+0x94/0x12e virtnet_poll+0x15d/0x315 [virtio_net] __napi_poll+0x2c/0x1c9 net_rx_action+0xe6/0x1fb __do_softirq+0x115/0x2d8 run_ksoftirqd+0x18/0x20 smpboot_thread_fn+0x183/0x19c ? smpboot_unregister_percpu_thread+0x66/0x66 kthread+0x10a/0x10f ? kthread_mod_delayed_work+0xb6/0xb6 ret_from_fork+0x22/0x30 ---[ end trace 49f61b07f775fd2b ]--- dst_release: dst:00000000c02d677a refcnt:-1 dst_release underflow (CVE-2021-47222)

  - 已修复 Linux 内核中的下列漏洞：IB/mlx5: Fix initializing CQ fragments buffer The function init_cq_frag_buf() can be called to initialize the current CQ fragments buffer cq->buf, or the temporary cq->resize_buf that is filled during CQ resize operation. However, the offending commit started to use function get_cqe() for getting the CQEs, the issue with this change is that get_cqe() always returns CQEs from cq->buf, which leads us to initialize the wrong buffer, and in case of enlarging the CQ we try to access elements beyond the size of the current cq->buf and eventually hit a kernel panic. [exception RIP: init_cq_frag_buf+103] [ffff9f799ddcbcd8] mlx5_ib_resize_cq at ffffffffc0835d60 [mlx5_ib] [ffff9f799ddcbdb0] ib_resize_cq at ffffffffc05270df [ib_core] [ffff9f799ddcbdc0] llt_rdma_setup_qp at ffffffffc0a6a712 [llt] [ffff9f799ddcbe10] llt_rdma_cc_event_action at ffffffffc0a6b411 [llt] [ffff9f799ddcbe98] llt_rdma_client_conn_thread at ffffffffc0a6bb75 [llt] [ffff9f799ddcbec8] kthread at ffffffffa66c5da1 [ffff9f799ddcbf50] ret_from_fork_nospec_begin at ffffffffa6d95ddd Fix it by getting the needed CQE by calling mlx5_frag_buf_get_wqe() that takes the correct source buffer as a parameter. (CVE-2021-47261)

  - 已修复 Linux 内核中的下列漏洞：blk-cgroup: fix UAF by grabbing blkcg lock before destroying blkg pd KASAN reports a use-after-free report when doing fuzz test: [693354.104835] ================================================================== [693354.105094] BUG: KASAN: use-after-free in bfq_io_set_weight_legacy+0xd3/0x160 [693354.105336] Read of size 4 at addr ffff888be0a35664 by task sh/1453338 [693354.105607] CPU: 41 PID: 1453338 Comm: sh Kdump: loaded Not tainted 4.18.0-147 [693354.105610] Hardware name: Huawei 2288H V5/BC11SPSCB0, BIOS 0.81 07/02/2018 [693354.105612] Call Trace: [693354.105621] dump_stack+0xf1/0x19b [693354.105626] ? show_regs_print_info+0x5/0x5 [693354.105634] ? printk+0x9c/0xc3 [693354.105638] ? cpumask_weight+0x1f/0x1f [693354.105648] print_address_description+0x70/0x360 [693354.105654] kasan_report+0x1b2/0x330 [693354.105659] ? bfq_io_set_weight_legacy+0xd3/0x160 [693354.105665] ? bfq_io_set_weight_legacy+0xd3/0x160 [693354.105670] bfq_io_set_weight_legacy+0xd3/0x160 [693354.105675] ? bfq_cpd_init+0x20/0x20 [693354.105683] cgroup_file_write+0x3aa/0x510 [693354.105693] ? ___slab_alloc+0x507/0x540 [693354.105698] ? cgroup_file_poll+0x60/0x60 [693354.105702] ? 0xffffffff89600000 [693354.105708] ? usercopy_abort+0x90/0x90 [693354.105716] ? mutex_lock+0xef/0x180 [693354.105726] kernfs_fop_write+0x1ab/0x280 [693354.105732] ? cgroup_file_poll+0x60/0x60 [693354.105738] vfs_write+0xe7/0x230 [693354.105744] ksys_write+0xb0/0x140 [693354.105749] ? __ia32_sys_read+0x50/0x50 [693354.105760] do_syscall_64+0x112/0x370 [693354.105766] ? syscall_return_slowpath+0x260/0x260 [693354.105772] ? do_page_fault+0x9b/0x270 [693354.105779] ? prepare_exit_to_usermode+0xf9/0x1a0 [693354.105784] ? enter_from_user_mode+0x30/0x30 [693354.105793] entry_SYSCALL_64_after_hwframe+0x65/0xca [693354.105875] Allocated by task 1453337: [693354.106001] kasan_kmalloc+0xa0/0xd0 [693354.106006] kmem_cache_alloc_node_trace+0x108/0x220 [693354.106010] bfq_pd_alloc+0x96/0x120 [693354.106015] blkcg_activate_policy+0x1b7/0x2b0 [693354.106020] bfq_create_group_hierarchy+0x1e/0x80 [693354.106026] bfq_init_queue+0x678/0x8c0 [693354.106031] blk_mq_init_sched+0x1f8/0x460 [693354.106037] elevator_switch_mq+0xe1/0x240 [693354.106041] elevator_switch+0x25/0x40 [693354.106045] elv_iosched_store+0x1a1/0x230 [693354.106049] queue_attr_store+0x78/0xb0 [693354.106053] kernfs_fop_write+0x1ab/0x280 [693354.106056] vfs_write+0xe7/0x230 [693354.106060] ksys_write+0xb0/0x140 [693354.106064] do_syscall_64+0x112/0x370 [693354.106069] entry_SYSCALL_64_after_hwframe+0x65/0xca [693354.106114] Freed by task 1453336:
    [693354.106225] __kasan_slab_free+0x130/0x180 [693354.106229] kfree+0x90/0x1b0 [693354.106233] blkcg_deactivate_policy+0x12c/0x220 [693354.106238] bfq_exit_queue+0xf5/0x110 [693354.106241] blk_mq_exit_sched+0x104/0x130 [693354.106245] __elevator_exit+0x45/0x60 [693354.106249] elevator_switch_mq+0xd6/0x240 [693354.106253] elevator_switch+0x25/0x40 [693354.106257] elv_iosched_store+0x1a1/0x230 [693354.106261] queue_attr_store+0x78/0xb0 [693354.106264] kernfs_fop_write+0x1ab/0x280 [693354.106268] vfs_write+0xe7/0x230 [693354.106271] ksys_write+0xb0/0x140 [693354.106275] do_syscall_64+0x112/0x370 [693354.106280] entry_SYSCALL_64_after_hwframe+0x65/0xca [693354.106329] The buggy address belongs to the object at ffff888be0a35580 which belongs to the cache kmalloc-1k of size 1024 [693354.106736] The buggy address is located 228 bytes inside of 1024-byte region [ffff888be0a35580, ffff888be0a35980) [693354.107114] The buggy address belongs to the page:
    [693354.107273] page:ffffea002f828c00 count:1 mapcount:0 mapping:ffff888107c17080 index:0x0 compound_mapcount: 0 [693354.107606] flags: 0x17ffffc0008100(slab|head) [693354.107760] raw:
    0017ffffc0008100 ffffea002fcbc808 ffffea0030bd3a08 ffff888107c17080 [693354.108020] r ---truncated--- (CVE-2021-47379)

  - 已修复 Linux 内核中的下列漏洞：ext4: block range must be validated before use in ext4_mb_clear_bb() Block range to free is validated in ext4_free_blocks() using ext4_inode_block_valid() and then it's passed to ext4_mb_clear_bb(). However in some situations on bigalloc file system the range might be adjusted after the validation in ext4_free_blocks() which can lead to troubles on corrupted file systems such as one found by syzkaller that resulted in the following BUG kernel BUG at fs/ext4/ext4.h:3319! PREEMPT SMP NOPTI CPU: 28 PID: 4243 Comm: repro Kdump: loaded Not tainted 5.19.0-rc6+ #1 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1.fc35 04/01/2014 RIP: 0010:ext4_free_blocks+0x95e/0xa90 Call Trace: <TASK> ? lock_timer_base+0x61/0x80 ?
    __es_remove_extent+0x5a/0x760 ? __mod_timer+0x256/0x380 ? ext4_ind_truncate_ensure_credits+0x90/0x220 ext4_clear_blocks+0x107/0x1b0 ext4_free_data+0x15b/0x170 ext4_ind_truncate+0x214/0x2c0 ?
    _raw_spin_unlock+0x15/0x30 ? ext4_discard_preallocations+0x15a/0x410 ? ext4_journal_check_start+0xe/0x90 ?
    __ext4_journal_start_sb+0x2f/0x110 ext4_truncate+0x1b5/0x460 ? __ext4_journal_start_sb+0x2f/0x110 ext4_evict_inode+0x2b4/0x6f0 evict+0xd0/0x1d0 ext4_enable_quotas+0x11f/0x1f0 ext4_orphan_cleanup+0x3de/0x430 ? proc_create_seq_private+0x43/0x50 ext4_fill_super+0x295f/0x3ae0 ? snprintf+0x39/0x40 ? sget_fc+0x19c/0x330 ? ext4_reconfigure+0x850/0x850 get_tree_bdev+0x16d/0x260 vfs_get_tree+0x25/0xb0 path_mount+0x431/0xa70 __x64_sys_mount+0xe2/0x120 do_syscall_64+0x5b/0x80 ? do_user_addr_fault+0x1e2/0x670 ? exc_page_fault+0x70/0x170 entry_SYSCALL_64_after_hwframe+0x46/0xb0 RIP:
    0033:0x7fdf4e512ace Fix it by making sure that the block range is properly validated before used every time it changes in ext4_free_blocks() or ext4_mb_clear_bb(). (CVE-2022-50021)

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

远程主机上安装的内核版本低于 5.4.156-83.273。因此，会受到 ALAS2KERNEL-5.4-2025-099 公告中提及的多个漏洞影响。

    在用户使用 OverlayFS 以特定方式重命名的方式中，发现访问 Linux 内核 OverlayFS 子系统中的文件对象时存在争用条件。本地用户可利用此缺陷导致系统崩溃。
    (CVE-2021-20321)

    在 Linux 内核中发现一个缺陷。ccp-ops crypto 驱动程序中的内存泄漏可允许攻击者造成拒绝服务。此缺陷与较早版本的 CVE-2019-18808 类似此漏洞最大的威胁在于系统可用性。(CVE-2021-3744)

    在 Linux 内核的 ccp_run_aes_gcm_cmd() 函数中发现内存泄漏缺陷，攻击者可利用此缺陷造成拒绝服务。此漏洞与早先的 CVE-2019-18808 类似。此漏洞最大的威胁在于系统可用性。(CVE-2021-3764)

    在 Linux 内核的 bpf 的 kernel/bpf/stackmap.c 的 prealloc_elems_and_freelist 中发现越界 (OOB) 内存写入缺陷。此缺陷用于计算大小的乘法运算可导致整数溢出，具有特殊用户权限的本地攻击者可获得对越界内存的访问权限，从而导致系统崩溃或内部内核泄漏信息。(CVE-2021-41864)

    在 Linux 内核中，以下漏洞已修复：

    binder：确保 fd closes 完整 (CVE-2021-47360)

    在 Linux 内核中，以下漏洞已修复：

    irqchip/gic-v3-its：修复因错误引起的潜在 VPE 泄漏 (CVE-2021-47373)

    在 Linux 内核中，以下漏洞已修复：

    blktrace：修复被 sysfs 删除之后 blk_trace 访问中的释放后使用问题 (CVE-2021-47375)

    在 Linux 内核中，以下漏洞已修复：

    bpf：添加调用 kvcalloc() 前的超大检查 (CVE-2021-47376)

    在 Linux 内核中，以下漏洞已修复：

    blk-cgroup：通过在破坏 blkg pd 之前获取 blkcg 锁定来修复 UAF (CVE-2021-47379)

    在 Linux 内核中，以下漏洞已修复：

    tty：修复 imageblit 中的 vmalloc 访问越界问题  (CVE-2021-47383)

    在 Linux 内核中，以下漏洞已修复：

    hwmon：(w83793) 通过移除不必要的结构字段来修复空指针取消引用 (CVE-2021-47384)

    在 Linux 内核中，以下漏洞已修复：

    hwmon(w83792d) 通过删除不必要的结构字段修复空指针取消引用 (CVE-2021-47385)

    在 Linux 内核中，以下漏洞已修复：

    hwmon：(w83791d) 通过移除不必要的结构字段来修复空指针取消引用 (CVE-2021-47386)

    在 Linux 内核中，以下漏洞已修复：

    cpufreq：schedutil：使用 kobject release() 方法释放 sugov_tunables (CVE-2021-47387)

    在 Linux 内核中，以下漏洞已修复：

    sctp如果 skb_header_pointer 在 sctp_rcv_ootb 中返回 NULL 则中断 (CVE-2021-47397)

    在 Linux 内核中，以下漏洞已修复：

    net：sched：flower：使用 rcu 保护 fl_walk() (CVE-2021-47402)

    在 Linux 内核中，以下漏洞已修复：

    HID：betop：修复 betop_probe 中的 slab-out-of-bound 写入 (CVE-2021-47404)

    在 Linux 内核中，以下漏洞已修复：

    HIDusbhid释放 usbhid_stop 中的 raw_report 缓冲区 (CVE-2021-47405)

    在 Linux 内核中，以下漏洞已修复：

    phymdio修复内存泄漏 (CVE-2021-47416)

    在 Linux 内核中，以下漏洞已修复：

    net_sched修复 fifo_set_limit() 中的空取消引用 (CVE-2021-47418)

    在 Linux 内核中，以下漏洞已修复：

    i40e修复未初始化的 misc IRQ 向量释放 (CVE-2021-47424)

    在 Linux 内核中，以下漏洞已修复：

    i2cacpi修复重新配置设备添加中的资源泄漏 (CVE-2021-47425)

    在 Linux 内核中，以下漏洞已修复：

    xhci修复了中止命令时的命令环指针损坏 (CVE-2021-47434)

    在 Linux 内核中，以下漏洞已修复：

    can：j1939：j1939_netdev_start()：修复 j1939_priv 的 rx_kref 中的释放后使用问题 (CVE-2021-47459)

    在 Linux 内核中，以下漏洞已修复：

    ocfs2修复内联格式转换后的数据损坏CVE-2021-47460

    在 Linux 内核中，以下漏洞已修复：

    audit：修复 audit_filter_rules 中可能存在的空指针取消引用漏洞 (CVE-2021-47464)

    在 Linux 内核中，以下漏洞已修复：

    mmslub修复 kmem_cache_open() 中的潜在内存泄漏 (CVE-2021-47466)

    在 Linux 内核中，以下漏洞已修复：

    nvmem：修复字节大小单元格的位移越界 (UBSAN) 问题 (CVE-2021-47497)

Tenable 已直接从测试产品的安全公告中提取上述描述块。

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

ID	名称	产品	系列	发布时间	最近更新时间	严重程度
230168	Linux Distros 未修补的漏洞: CVE-2021-47379	Nessus	Misc.	2025/3/5	2026/7/17	high
160447	Amazon Linux 2：内核 (ALASKERNEL-5.10-2022-007)	Nessus	Amazon Linux Local Security Checks	2022/5/2	2026/2/26	critical
351793	CentOS Linux 8.5 [TuxCare] 安全更新：bpftool / kernel / kernel-core / kernel-cross-headers / 等多个漏洞（CENTOS8.5：CLSA-2026：1783414155）	Nessus	CentOS Local Security Checks	2026/9/30	2026/9/30	high
241626	Ubuntu 14.04 LTS / 16.04 LTS / 18.04 LTS：Linux 内核漏洞 (USN-7627-1)	Nessus	Ubuntu Local Security Checks	2025/7/9	2025/7/9	high
352525	CentOS Linux 8.4 [TuxCare] 安全更新：bpftool / kernel / kernel-core / kernel-cross-headers / 等多个漏洞（CENTOS8.4：CLSA-2026：1783414634）	Nessus	CentOS Local Security Checks	2026/9/30	2026/9/30	high
235794	Amazon Linux 2：内核 (ALASKERNEL-5.4-2025-099)	Nessus	Amazon Linux Local Security Checks	2025/5/13	2026/2/26	high

检测

插件搜索

high

critical

high

high

high

high