Rocky Linux 9.6 [TuxCare] 安全性更新:kernel / kernel-64k / kernel-64k-core / kernel-64k-debug / etc 多個弱點 (ALMALINUX9.6:CLSA-2026:1783793262)

high Nessus Plugin ID 359559

概要

Rocky Linux 主機缺少一個或多個安全性更新。

說明

Rocky Linux 9.6 主機已安裝的套件會受到 TuxCare ALMALINUX9.6:CLSA-2026:1783793262 公告中提及的多個弱點影響。

- 已解決 Linux 核心中的下列弱點:rtmutex: Use waiter::task instead of current in remove_waiter() remove_waiter() is used by the slowlock paths, but it is also used for proxy-lock rollback in rt_mutex_start_proxy_lock() when invoked from futex_requeue(). In the latter case waiter::task is not current, but remove_waiter() operates on current for the dequeue operation. That results in several problems: 1) the rbtree dequeue happens without waiter::task::pi_lock being held 2) the waiter task's pi_blocked_on state is not cleared, which leaves a dangling pointer primed for UAF around.
3) rt_mutex_adjust_prio_chain() operates on the wrong top priority waiter task Use waiter::task instead of current in all related operations in remove_waiter() to cure those problems. [ tglx: Fixup rt_mutex_adjust_prio_chain(), add a comment and amend the changelog ] (CVE-2026-43499)

- 已解決 Linux 核心中的下列弱點:eventpoll: fix ep_remove struct eventpoll / struct file UAF ep_remove() (via ep_remove_file()) cleared file->f_ep under file->f_lock but then kept using @file inside the critical section (is_file_epoll(), hlist_del_rcu() through the head, spin_unlock). A concurrent __fput() taking the eventpoll_release() fastpath in that window observed the transient NULL, skipped eventpoll_release_file() and ran to f_op->release / file_free(). For the epoll-watches-epoll case, f_op->release is ep_eventpoll_release() -> ep_clear_and_put() -> ep_free(), which kfree()s the watched struct eventpoll. Its embedded ->refs hlist_head is exactly where epi->fllink.pprev points, so the subsequent hlist_del_rcu()'s *pprev = next scribbles into freed kmalloc-192 memory. In addition, struct file is SLAB_TYPESAFE_BY_RCU, so the slot backing @file could be recycled by alloc_empty_file() -- reinitializing f_lock and f_ep -- while ep_remove() is still nominally inside that lock. The upshot is an attacker-controllable kmem_cache_free() against the wrong slab cache. Pin @file via epi_fget() at the top of ep_remove() and gate the critical section on the pin succeeding. With the pin held @file cannot reach refcount zero, which holds __fput() off and transitively keeps the watched struct eventpoll alive across the hlist_del_rcu() and the f_lock use, closing both UAFs. If the pin fails @file has already reached refcount zero and its __fput() is in flight. Because we bailed before clearing f_ep, that path takes the eventpoll_release() slow path into eventpoll_release_file() and blocks on ep->mtx until the waiter side's ep_clear_and_put() drops it. The bailed epi's share of ep->refcount stays intact, so the trailing ep_refcount_dec_and_test() in ep_clear_and_put() cannot free the eventpoll out from under eventpoll_release_file(); the orphaned epi is then cleaned up there. A successful pin also proves we are not racing eventpoll_release_file() on this epi, so drop the now-redundant re-check of epi->dying under f_lock. The cheap lockless READ_ONCE(epi->dying) fast-path bailout stays. (CVE-2026-46242)

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 ALMALINUX9.6:CLSA-2026:1783793262 中的指引更新受影響的套件。

另請參閱

https://cve.tuxcare.com/els/releases/CLSA-2026:1783793262

http://www.nessus.org/u?3c8f3bae

Plugin 詳細資訊

嚴重性: High

ID: 359559

檔案名稱: tuxcare_rocky_linux_9.6_CLSA-2026-1783793262.nasl

版本: 1.4

類型: Local

已發布: 2026/10/1

已更新: 2026/10/22

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: Critical

分數: 9.5

百分位數: 99.87

Vendor

Vendor Severity: Important

CVSS v2

風險因素: Medium

基本分數: 6.8

時間性分數: 5.9

媒介: CVSS2#AV:L/AC:L/Au:S/C:C/I:C/A:C

CVSS 評分資料來源: CVE-2026-46242

CVSS v3

風險因素: High

基本分數: 7.8

時間性分數: 7.5

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:H/RL:O/RC:C

弱點資訊

必要的 KB 項目: Host/local_checks_enabled, Host/cpu, Host/RockyLinux/release, Host/RockyLinux/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: 2026/7/11

弱點發布日期: 2026/5/21

參考資訊

CVE: CVE-2026-43499, CVE-2026-46242

CLSA: 2026:1783793262