CentOS Linux 8.5 [TuxCare] 安全性更新:bpftool / kernel / kernel-core / kernel-cross-headers / etc 多個弱點 (CENTOS8.5:CLSA-2026:1793359087)

critical Nessus Plugin ID 374206

概要

CentOS Linux 主機缺少一個或多個安全性更新。

說明

CentOS Linux 8.5 主機已安裝的套件會受到 TuxCare CENTOS8.5:CLSA-2026:1793359087 公告中提及的多個弱點影響。

- 已解決 Linux 核心中的下列弱點:net/sched: cls_api: remove block_cb from driver_list before freeing Error handler of tcf_block_bind() frees the whole bo->cb_list on error.
However, by that time the flow_block_cb instances are already in the driver list because driver ndo_setup_tc() callback is called before that up the call chain in tcf_block_offload_cmd(). This leaves dangling pointers to freed objects in the list and causes use-after-free[0]. Fix it by also removing flow_block_cb instances from driver_list before deallocating them. [0]: [ 279.868433] ================================================================== [ 279.869964] BUG: KASAN: slab-use-after-free in flow_block_cb_setup_simple+0x631/0x7c0 [ 279.871527] Read of size 8 at addr ffff888147e2bf20 by task tc/2963 [ 279.873151] CPU: 6 PID: 2963 Comm: tc Not tainted 6.3.0-rc6+ #4 [ 279.874273] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 [279.876295] Call Trace: [ 279.876882] <TASK> [ 279.877413] dump_stack_lvl+0x33/0x50 [ 279.878198] print_report+0xc2/0x610 [ 279.878987] ? flow_block_cb_setup_simple+0x631/0x7c0 [ 279.879994] kasan_report+0xae/0xe0 [ 279.880750] ? flow_block_cb_setup_simple+0x631/0x7c0 [ 279.881744] ? mlx5e_tc_reoffload_flows_work+0x240/0x240 [mlx5_core] [ 279.883047] flow_block_cb_setup_simple+0x631/0x7c0 [ 279.884027] tcf_block_offload_cmd.isra.0+0x189/0x2d0 [ 279.885037] ? tcf_block_setup+0x6b0/0x6b0 [279.885901] ? mutex_lock+0x7d/0xd0 [ 279.886669] ? __mutex_unlock_slowpath.constprop.0+0x2d0/0x2d0 [279.887844] ? ingress_init+0x1c0/0x1c0 [sch_ingress] [ 279.888846] tcf_block_get_ext+0x61c/0x1200 [279.889711] ingress_init+0x112/0x1c0 [sch_ingress] [ 279.890682] ? clsact_init+0x2b0/0x2b0 [sch_ingress] [279.891701] qdisc_create+0x401/0xea0 [ 279.892485] ? qdisc_tree_reduce_backlog+0x470/0x470 [ 279.893473] tc_modify_qdisc+0x6f7/0x16d0 [ 279.894344] ? tc_get_qdisc+0xac0/0xac0 [ 279.895213] ? mutex_lock+0x7d/0xd0 [ 279.896005] ? __mutex_lock_slowpath+0x10/0x10 [ 279.896910] rtnetlink_rcv_msg+0x5fe/0x9d0 [ 279.897770] ? rtnl_calcit.isra.0+0x2b0/0x2b0 [ 279.898672] ? __sys_sendmsg+0xb5/0x140 [ 279.899494] ? do_syscall_64+0x3d/0x90 [ 279.900302] ? entry_SYSCALL_64_after_hwframe+0x46/0xb0 [ 279.901337] ? kasan_save_stack+0x2e/0x40 [ 279.902177] ? kasan_save_stack+0x1e/0x40 [ 279.903058] ? kasan_set_track+0x21/0x30 [ 279.903913] ? kasan_save_free_info+0x2a/0x40 [ 279.904836] ?
____kasan_slab_free+0x11a/0x1b0 [ 279.905741] ? kmem_cache_free+0x179/0x400 [ 279.906599] netlink_rcv_skb+0x12c/0x360 [ 279.907450] ? rtnl_calcit.isra.0+0x2b0/0x2b0 [ 279.908360] ? netlink_ack+0x1550/0x1550 [ 279.909192] ? rhashtable_walk_peek+0x170/0x170 [ 279.910135] ? kmem_cache_alloc_node+0x1af/0x390 [ 279.911086] ? _copy_from_iter+0x3d6/0xc70 [ 279.912031] netlink_unicast+0x553/0x790 [ 279.912864] ? netlink_attachskb+0x6a0/0x6a0 [ 279.913763] ? netlink_recvmsg+0x416/0xb50 [ 279.914627] netlink_sendmsg+0x7a1/0xcb0 [ 279.915473] ? netlink_unicast+0x790/0x790 [ 279.916334] ? iovec_from_user.part.0+0x4d/0x220 [ 279.917293] ? netlink_unicast+0x790/0x790 [ 279.918159] sock_sendmsg+0xc5/0x190 [ 279.918938]
____sys_sendmsg+0x535/0x6b0 [ 279.919813] ? import_iovec+0x7/0x10 [ 279.920601] ? kernel_sendmsg+0x30/0x30 [ 279.921423] ? __copy_msghdr+0x3c0/0x3c0 [ 279.922254] ? import_iovec+0x7/0x10 [ 279.923041]
___sys_sendmsg+0xeb/0x170 [ 279.923854] ? copy_msghdr_from_user+0x110/0x110 [ 279.924797] ?
___sys_recvmsg+0xd9/0x130 [ 279.925630] ? __perf_event_task_sched_in+0x183/0x470 [ 279.926656] ?
___sys_sendmsg+0x170/0x170 [ 279.927529] ? ctx_sched_in+0x530/0x530 [ 279.928369] ? update_curr+0x283/0x4f0 [ 279.929185] ? perf_event_update_userpage+0x570/0x570 [ 279.930201] ?
__fget_light+0x57/0x520 [ 279.931023] ? __switch_to+0x53d/0xe70 [ 27 ---truncated--- (CVE-2023-54193)

- 已解決 Linux 核心中的下列弱點:pNFS: Fix use-after-free in pnfs_update_layout() When hitting the NFS_LAYOUT_RETURN branch in pnfs_update_layout(), the code calls pnfs_prepare_to_retry_layoutget(lo). If it succeeds, pnfs_put_layout_hdr(lo) is called before trace_pnfs_update_layout(), which still references 'lo'. This results in a use-after-free when the tracepoint accesses lo's fields. Fix this by moving the tracepoint call before pnfs_put_layout_hdr(lo).
(CVE-2026-63800)

- 已解決 Linux 核心中的下列弱點:Bluetooth: HIDP: fix missing length checks in hidp_input_report() hidp_input_report() reads keyboard and mouse payload data from an skb without first verifying that skb->len contains enough data. hidp_recv_intr_frame() pulls the 1-byte HIDP header before dispatching to hidp_input_report(). If a paired device sends a truncated packet, the handler reads beyond the valid skb data, resulting in an out-of-bounds read of skb data. The OOB bytes may be interpreted as phantom key presses or spurious mouse movement. Replace the open-coded length tracking and pointer arithmetic with skb_pull_data() calls. skb_pull_data() returns NULL if the requested bytes are not present, eliminating the need for a manual size variable and the separate skb->len guard. (CVE-2026-63947)

- 已解決 Linux 核心中的下列弱點:tunnels: load network headers after skb_cow() in iptunnel_pmtud_build_icmp[v6]() Sashiko found that iptunnel_pmtud_build_icmp() and iptunnel_pmtud_build_icmpv6() were caching ip_hdr() and ipv6_hdr() before an skb_cow() call which can reallocate skb->head. Fix this possible UAF by initializing the local variables after the skb_cow() call.
Remove skb_reset_network_header() calls which were not needed. (CVE-2026-63994)

- 已解決 Linux 核心中的下列弱點:net: openvswitch: fix potential UAF on meter attach failure While attaching a newly created meter attach_meter() function makes the new meter visible to other CPUs but can still fail afterwards. On failure, it detaches the meter back and returns an error. However, this is an unexpected behavior for the ovs_meter_cmd_set() that uses a plain kfree(meter) on attach failure without waiting for RCU readers to stop using it, assuming it was never visible. This is never a problem for ovs-vswitchd as it always creates meters before creating any flows that use them. But the UAF can be triggered with a custom application using uAPI: BUG: KASAN: slab-use-after-free in ovs_meter_execute (net/openvswitch/meter.c:653) Read of size 8 at addr ffff88810d152650 by task meter/2508 Call Trace: ovs_meter_execute (net/openvswitch/meter.c:653) do_execute_actions (net/openvswitch/actions.c:1407) ovs_execute_actions (net/openvswitch/actions.c:1584) ovs_packet_cmd_execute (net/openvswitch/datapath.c:703) ... netlink_sendmsg (af_netlink.c:1900) Allocated by task 2519: __kasan_kmalloc (mm/kasan/common.c:398 mm/kasan/common.c:415) ovs_meter_cmd_set (net/openvswitch/meter.c:422) ... netlink_sendmsg (af_netlink.c:1900) Freed by task 2519: kfree (mm/slub.c:2705 mm/slub.c:6405 mm/slub.c:6720) ovs_meter_cmd_set (net/openvswitch/meter.c:479) ...
netlink_sendmsg (af_netlink.c:1900) Fix that by making sure attach_meter() doesn't make the meter visible until all the checks are done and the function can't fail anymore. This also makes sure the hash value is calculated after the potential re-sizing of the table. Reported by Trend Micro's Zero Day Initiative as ZDI-CAN-31642. (CVE-2026-74465)

請注意,Nessus 並未測試這些問題,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

根據 TuxCare 公告 CENTOS8.5:CLSA-2026:1793359087 中的指引更新受影響的套件。

另請參閱

https://cve.tuxcare.com/els/releases/CLSA-2026:1793359087

http://www.nessus.org/u?dd137024

Plugin 詳細資訊

嚴重性: Critical

ID: 374206

檔案名稱: tuxcare_centos_8.5_CLSA-2026-1793359087.nasl

版本: 1.1

類型: Local

代理程式: unix

已發布: 2026/10/30

已更新: 2026/10/30

支援的感應器: Nessus Agent, Continuous Assessment, Tenable Cloud Security, Tenable Self-Hosted Container Security, Nessus

風險資訊

VPR

風險因素: High

分數: 7.9

百分位數: 99.32

Vendor

Vendor Severity: Important

CVSS v2

風險因素: Critical

基本分數: 10

時間性分數: 7.8

媒介: CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C

CVSS 評分資料來源: CVE-2026-98432

CVSS v3

風險因素: Critical

基本分數: 9.8

時間性分數: 8.8

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

時間媒介: CVSS:3.0/E:P/RL:O/RC:C

弱點資訊

必要的 KB 項目: Host/local_checks_enabled, Host/CentOS/release, Host/CentOS/rpm-list, Host/OS/extended-third-party

可被惡意程式利用: true

可輕鬆利用: Exploits are available

修補程式發佈日期: 2026/10/30

弱點發布日期: 2021/7/21

參考資訊

CVE: CVE-2023-54193, CVE-2026-63800, CVE-2026-63947, CVE-2026-63994, CVE-2026-74465, CVE-2026-89533, CVE-2026-98417, CVE-2026-98432, CVE-2026-99082

CLSA: 2026:1793359087