CentOS Linux 7 [TuxCare] 安全性更新：bpftool / kernel / kernel-debug / kernel-debug-devel / kernel-devel / etc多個弱點 （CENTOS7：CLSA-2026：1775657929）
high Nessus Plugin ID 361381
語言:
概要
CentOS Linux 主機缺少一個或多個安全性更新。說明
CentOS Linux 7 主機已安裝的套件會受到 TuxCare CENTOS7：CLSA-2026：1775657929 公告中提及的多個弱點影響。- 已解決 Linux 核心中的下列弱點：ovl: Filter invalid inodes with missing lookup function Add a check to the ovl_dentry_weird() function to prevent the processing of directory inodes that lack the lookup function. This is important because such inodes can cause errors in overlayfs when passed to the lowerstack. (CVE-2024-56570)
- 已解決 Linux 核心中的下列弱點：NFSv4/pNFS: Clear NFS_INO_LAYOUTCOMMIT in pnfs_mark_layout_stateid_invalid Fixes a crash when layout is null during this call stack: write_inode
-> nfs4_write_inode -> pnfs_layoutcommit_inode pnfs_set_layoutcommit relies on the lseg refcount to keep the layout around. Need to clear NFS_INO_LAYOUTCOMMIT otherwise we might attempt to reference a null layout. (CVE-2025-68349)
- 已解決 Linux 核心中的下列弱點：net/sched: Enforce that teql can only be used as root qdisc Design intent of teql is that it is only supposed to be used as root qdisc. We need to check for that constraint. Although not important, I will describe the scenario that unearthed this issue for the curious. GangMin Kim <[email protected]> managed to concot a scenario as follows: ROOT qdisc 1:0 (QFQ) class 1:1 (weight=15, lmax=16384) netem with delay 6.4s class 1:2 (weight=1, lmax=1514) teql GangMin sends a packet which is enqueued to 1:1 (netem). Any invocation of dequeue by QFQ from this class will not return a packet until after 6.4s. In the meantime, a second packet is sent and it lands on 1:2. teql's enqueue will return success and this will activate class 1:2. Main issue is that teql only updates the parent visible qlen (sch->q.qlen) at dequeue. Since QFQ will only call dequeue if peek succeeds (and teql's peek always returns NULL), dequeue will never be called and thus the qlen will remain as 0. With that in mind, when GangMin updates 1:2's lmax value, the qfq_change_class calls qfq_deact_rm_from_agg. Since the child qdisc's qlen was not incremented, qfq fails to deactivate the class, but still frees its pointers from the aggregate. So when the first packet is rescheduled after 6.4 seconds (netem's delay), a dangling pointer is accessed causing GangMin's causing a UAF. (CVE-2026-23074)
- 已解決 Linux 核心中的下列弱點：ALSA: usb-audio: Fix use-after-free in snd_usb_mixer_free() When snd_usb_create_mixer() fails, snd_usb_mixer_free() frees mixer->id_elems but the controls already added to the card still reference the freed memory. Later when snd_card_register() runs, the OSS mixer layer calls their callbacks and hits a use-after-free read. Call trace:
get_ctl_value+0x63f/0x820 sound/usb/mixer.c:411 get_min_max_with_quirks.isra.0+0x240/0x1f40 sound/usb/mixer.c:1241 mixer_ctl_feature_info+0x26b/0x490 sound/usb/mixer.c:1381 snd_mixer_oss_build_test+0x174/0x3a0 sound/core/oss/mixer_oss.c:887 ... snd_card_register+0x4ed/0x6d0 sound/core/init.c:923 usb_audio_probe+0x5ef/0x2a90 sound/usb/card.c:1025 Fix by calling snd_ctl_remove() for all mixer controls before freeing id_elems. We save the next pointer first because snd_ctl_remove() frees the current element. (CVE-2026-23089)
- 已解決 Linux 核心中的下列弱點：ALSA: aloop: Fix racy access at PCM trigger The PCM trigger callback of aloop driver tries to check the PCM state and stop the stream of the tied substream in the corresponding cable. Since both check and stop operations are performed outside the cable lock, this may result in UAF when a program attempts to trigger frequently while opening/closing the tied stream, as spotted by fuzzers. For addressing the UAF, this patch changes two things: - It covers the most of code in loopback_check_format() with cable->lock spinlock, and add the proper NULL checks. This avoids already some racy accesses. - In addition, now we try to check the state of the capture PCM stream that may be stopped in this function, which was the major pain point leading to UAF. (CVE-2026-23191)
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 CENTOS7：CLSA-2026：1775657929 中的指引更新受影響的套件。另請參閱
Plugin 詳細資訊
嚴重性: High
ID: 361381
檔案名稱: tuxcare_centos_7_CLSA-2026-1775657929.nasl
版本: 1.1
類型: Local
代理程式: unix
已發布: 2026/10/1
已更新: 2026/10/1
支援的感應器: Continuous Assessment, Nessus Agent, Tenable Cloud Security, Tenable Self-Hosted Container Security, Nessus
風險資訊
VPR
風險因素: Medium
分數: 6.9
百分位數: 97.08
Vendor
Vendor Severity: Important
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-2026-23193
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
必要的 KB 項目: Host/OS/extended-third-party, Host/local_checks_enabled, Host/CentOS/release, Host/CentOS/rpm-list
可輕鬆利用: No known exploits are available
修補程式發佈日期: 2026/4/8
弱點發布日期: 2023/12/12
參考資訊
CVE: CVE-2024-56570, CVE-2025-68349, CVE-2026-23074, CVE-2026-23089, CVE-2026-23191, CVE-2026-23193, CVE-2026-23204
CLSA: 2026:1775657929